The Zeerusty cultural counterpart to the Retro Rocket, the Flying Saucer, and the Tin Can Robot; usually seen in older media and Retraux works, these are aliens (usually but not exclusively humanoids) or future humans that speak, behave or function more like robots or Mechanical Lifeforms... despite being at least partially or even wholly organic. If they have a society, it is heavily mechanized, and characterized by its rigidity. However, they differ from Mechanical Lifeforms in that they are either fully biological organisms or only partially cybernetic.
This probably comes from a classic way of distinguishing aliens from humans in older science fiction: give the aliens machine-like characteristics and values, and suddenly what would otherwise be just, a Human Alien, a Rubber Forehead Alien, or some guy in a rubber suit seems much more exotic when compared to regular old humans.
Aliens like this may have some kind of Hive Mind, have a Hive Caste System, or be controlled by an Artificial Intelligence (these frequently overlap). However they are just as often portrayed as individuals, though perhaps unimaginative ones. They will often use mechanical sounding terms, combined with typical Spock Speak or Robo Speak and Sesquipedalian Loquaciousness to describe biological characteristics and processes ("energy extraction" or similar for eating; "waste extraction" for urination/defecation, "databanks" for memory, etc...), or their equivalents. Very often they will speak in a Creepy Monotone. Sometimes the reason that such a culture exists is because the entire species experienced a civilization-wide case of Cybernetics Eat Your Soul, often as a response to some kind of large scale catastrophe. In the case of organics though, they will skip the cybernetic stage and adopt a mechanistic society in response to catastrophe, with similar consequences as Cybernetics Eat Your Soul.
They are distinct from Mechanical Lifeforms in that they do not have to be even partially mechanical themselves, only that they model their behavior and/or culture on that of robots or machines. In some cases, it may not be clear whether they are Mechanical Lifeforms or not.
In-universe, the aliens might either think of themselves as living machines, place a high cultural value on the characteristics of machines that are not reflected by organic beings (efficiency, organization, emotionlessness, etc...), or maybe held in bondage by a machine like a supercomputer.
Whether or not the aliens have some mechanical components and count as Cyborgs varies from work to work; it is not a requirement to be an example of this trope, but it is commonly invoked (and just as commonly kept ambiguous).
Note that this often overlaps with Ditto Aliens and occasionally Transhuman Aliens.
Extreme and malevolent examples tend to be BionicZombies (and can emulate either the classic Zombie stereotype or the more modern viral Zombie trope).
More benevolent versions may be The Spock.
Contrast Mechanical Lifeforms, where the aliens actually are entirely mechanical, and may or may not possess a mechanistic culture like this.
Note that this is a cultural trope, having to do with social behavior primarily and physiology or hardware only secondarily. To be an example, the culture of the aliens (or future humans) must be mechanistic; cyborg aliens without a mechanistic culture would not count as examples.
The Martians in Santa Claus Conquers the Martians: Food Pill-eating, joyless, humorless humanoid creatures with metallic-green skin and distinctly robot-like headgear incorporated into their costume design; the dullness of their heavily mechanized lives results in their children getting addicted to joyful, cheery Earthling holiday television programming.
The Mondoshawan from The Fifth Element: are they beings wearing powered suits of armor, or are they Mechanical Lifeforms? It's pretty ambiguous. Then again, some of the dialog during Leeloo's reconstruction scene implies that the Mondoshawan have DNA (it's also implied that Leeloo, the titular "Fifth Element" and Living MacGuffin, had a form similar to a Mondoshawan prior to being reconstructed in human form, since the piece of her that they used to reconstruct her appeared to be a Mondoshawan hand).
Laughably bad MST3K fodder and Sci-Fi Cult classic film Robot Monster features Ro-Man... Appearing as a man in a gorilla suit with a deep sea diver's helmet, the alien invader's exact morphology is elusive. It seems to be a cyborg, it comes from an advanced civilization, it is able to resist radiation, and speaks in a typical roboticstyle monotonepopular at the time in B-movies. However they are not simply constructs or tools, as we learn in the scene where the earth stationed Ro-Man contacts the leader of the Ro-Men, who is a similar diving helmeted gorilla-bodied biped.
People who claim to have encountered The Men in Black frequently report that the individuals they encountered behaved in an odd, machine-like fashion, displayed an odd fascination with mundane objects, and spoke in unusual speech cadences, or a Creepy Monotone.
"Little Green Men" in 1950's pop culture often had highly regimented societies and had mechanistic speech, behavior and self-perceptions.
Similarly, the modern descendents of the Little Green Men Mythos, the modern-day Greys, are often described as being like organic robots or drones, and/or part of a Hive Caste System, sometimes even with a Hive Mind. In many iterations of the modern UFO Mythos, The Greys are also described as cold, soulless, or unemotional.
The Vogons from The Hitchhiker's Guide to the Galaxy are not-so little Green Men whose overly bureaucratized society, like the Hierarchy in Star Trek: Voyager, may be taken as a parody or a deconstruction of this trope, with the over-bureaucratization standing in for over-mechanization.
The main aliens in Bruce Coville's Space Brat books are stereotypical green humanoids with antennae who hatch from eggs. Their children are raised by computers and public officials, and many other elements of their society are highly impersonal.
The Meklar from the Line of Delirium series were originally The Reptilians, but they have embraced machine-like thinking, viewing everything organic as inferior, and each of them begins replacing body parts with cybernetics soon after birth, becoming fully Mechanical Lifeforms by the end of their natural life span.
Doctor Who: The Daleks and the Cybermen are both technically cyborg races that follow this trope; particularly the Cybermen. They both have robotic voices and overlap with Transhuman Aliens. They are both obsessed with machine-like efficiency, but the Daleks are dedicated to exterminating other species (especially humans and Time Lords), whereas the Cybermen are The Assimilator.
Star Trek: Several aliens, primarily from the original series:
The drone-like Lawgivers in "Return of the Archons." In that case, the drone-like humanoids were controlled by an intelligent supercomputer.
The original builders of the Androids on Exo III were also stated to have been a society of biological creatures who ruined their homeworld and retreated underground where they became a more mechanized, machine-like society.
The Kelvans from the Andromeda Galaxy are implied to have a culture like this; they are completely organic beings, but in their true form they experience none of the sensory distractions of humanoids, and consider themselves much more efficient. They go about trying to take over the Milky Way with very straightforward methods (transforming Kirk's crew into vulnerable dust-cubes that only their technology can restore to human form, for example) but without any of the typical Trek villains' hamminess. The Federation is saved from them by the fact that, when in artificial humanoid form, the Kelvans become Sense Freaks and can be incapacitated in a variety of ways, such as by the effects of alcohol or unfamiliar emotions like pleasure or jealousy.
The Eyemorg (humanoid female) society in the infamous episode "Spock's Brain" were totally reliant on a mechanized underground industrial complex run by advanced computers (for which purpose they tried to steal "Spock's Brain," because they lacked the knowledge to maintain this infrastructure themselves unless); this was in contrast to the primitive, Ice Age-like culture of males that lived on the surface.
The Fabrini who lived aboard a generational asteroid ship, which they all believed was actually a planet, were similarly run by an advanced, tyrannical computer called The Oracle. The Fabrini were less "rigidly mechanical" and more "rigidly traditional" though, the rigid traditions being enforced by The Oracle.
The Borg are a Hive Mind of Hollywood Cyborg aliens that otherwise follow this trope, using cybernetically augmented humanoid bodies only as cannon fodder and servitor units.
Vulcans sometimes have elements of this, but their culture is much more complex. Their education system, however, as briefly shown in Star Trek IV: The Voyage Home and more extensively in Star Trek (2009), is very much in line with this trope and plays like a callback to the uber-intellectual, emotionless aliens of older science fiction.
The Iyaarans, a species from a Season 7 episode of Star Trek: The Next Generation, play this trope absolutely straight, and also like a callback to aliens from older Sci-Fi: They are Ditto Aliens with rubber foreheads and jumpsuits; they lack cultural concepts like antagonism, love, joy, pleasure, crime, etc; they all appear male and reproduce asexually by something called post-cellular compounding, the exact mechanics of which are, fortunately, never detailed. Their diet is extremely bland, consisting of nutrient wafers, because they consider their need to eat as matter of sustenance only, not pleasure or enjoyment, like many other humanoids consider meals. Unlike most examples of this trope, however, they are very curious about other cultures, though they struggle to understand diverse cultures like the Federation.
Similarly, the cauliflower-headed humanoids that abducted Picard for study in an earlier episode were all identical with no concept of individual identity or leadership. What little was revealed about their society hinted at something like this trope.
The Bynars from the first season episode "11001001" are closely dependent on their computers for survival. They have implants that connect them to their planet's central computer, have "digital" names like One Zero and Zero One, live and work in binary pairs, have a language based on binary, and when their planet's central planetary computer is fried by a nearby supernova it almost wipes out the entire species.
The Hierarchy from Star Trek: Voyager are a callback/parody/possible deconstruction of this, with their heavily regimented, computerized society, costume design, and snotty behavior.
An episode of Lost in Space featured a mechanized society of humanoid cyborgs whose leader was a computer. They kidnapped Dr. Smith to repair the computer. They also had clock-like mechanisms on their chests which they could use to turn back or alter the flow of time.
Not a straight example, but played with in the reimagined Battlestar Galactica: The Cylon Civil War happens to a large degree because Six's and Cavil's factions disagree about whether their society of Artificial Humans should explore their humanity (Six's faction) or embrace their nature as machines and "be the best machines the Universe has ever seen" (Cavil's faction).
Cavil is a real hypocrite about this, though, and most of his behavior is due to the fact that he hates having been given human form when his creators could have just as easily designed him as an omniscient God-like A.I.
In the original show, the Cylons were originally meant to be reptilian humanoids who wore robot-like armor and spoke in synthesized, robot-like voices. By the time the Pilot was filmed, however, their backstory had been changed so that they were now the machine descendants of an extinct reptilian species.
Blake's 7 had the System, a civilization controlled by the three powerful defense computers of the three inhabited planets of their solar system, which built the starship DSV-1. The System was administered by Altas (either cyborgs, androids, or augmented humans) and black-armored guards that appeared to be cybernetically augmented humans. There were also thousands of human slaves, descendents of the people who had built the computers that had taken over their civilization.
Similarly, the Ultra of Ultraworld in Series 3 are blue-skinned humanoid creatures either summoned or created by Ultraworld (a living, artificial planet/giant computer centered around an enormous brain) to interact with captured starship crews, whom Ultraworld intends to absorb into its gestalt. They walk with a jerky gait and speak in odd, robot-like cadences. The "menials," assimilated humanoid servants, are also examples of this trope: their identity, memories and emotions are recorded on a tube and stored in a library. They behave mechanistically as they toil about, maintaining Ultraworld.
In the eighties science fiction series Otherworld, the Church of Artificial Intelligence filled this role for the Alternate Universe where the heroes, an American family on vacation in Egypt, founded themselves stranded. It was the state religion of a totalitarian government that enforced strict conformity through the Zone Troopers. More like this trope is what they were striving for though, than what they actually achieved.
The Observers from Fringe who are future descendants of humanity hint at this with their uniformity, odd behavior, Creepy Monotone speech, and severely dulled sense of taste in contrast to their subtle perceptions of the flow of time, play this and most of the original MIB Mythos, see above pretty straight (that is, up until the episode "Letters of Transit"). It's possible the Scientific Team September, August, et al were a part of was some kind of "scientific caste" in Observer society; the behavior of the "Overseer" Observers in the possible version of the year 2036 in the episode "Letters of Transit" were much more carnal and human-like, and did not seem to use the same Creepy Monotone (though one or more of those traits might be due to prolonged exposure to modern/Twenty Minutes into the Future human behavior).
There appear to be no female Observers (at least none have been seen so far), and how or if they reproduce has never been addressed. They are also Ditto Posthumans, being extremely uniform, even when they appear in large numbers. They all seem to wear variations on a suit and a decades-out-of-style hat; this also includes when they appear in large numbers; the episodes set in the future make it clear that all Observers dress like this, not just the members of September's Scientific Team.
Warhammer 40K has the Tau, organic aliens who have embraced machine culture enough to section their society into castes based on their given functions in life and where they come from. Even their names denote their particular traits.
The Starmen from Earthbound. They're visibly metallic and they have Robo Speak, but they're able to cast spells, and come back as ghosts, something one would not expect from robots.
The Machina race from the Xenoblade Chronicles RPG video game seem to be this.
The Space Pirates from the Metroid series of action adventures video games.
Five hats means that five tropers think it is ready to publish.
You are saying that you think this draft is ready to be published. That means the description is not ambiguous,
it doesn't duplicate an existing trope, there are at least three examples, and the title makes sense.
Is that what you meant to do?
You are saying this draft has a ready-to-publish hat it does not deserve and you are taking it back.