So a character wants to distinguish themselves from the rest of the pack. Catch Phrases are always a good way, since you don't need to see them in order to know who they are. But a single catch phrase is so boring.

The answer: just add a specific prefix/suffix onto words.

In some cases, they'll create new words with new meanings this way, but more often than not they're just the same word with that prefix/suffix tacked on, and no definition changes. Sometimes, also, other characters may start using these words as well, turning them into, in a manner, Borrowed Catchphrases or Share Phrases.

The ultimate of this trope is, unsurprisingly, McDonalds, who use their 'Mc' prefix on almost everything they sell. In their case, not only have their words made the general vernacular, but also their naming habits, as The Other Wiki has proven.

A Sub Trope of Catch Phrase. If used often enough, McVocab may become involuntary, ultimately turning into a Verbal Tic.

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Examples:

Live Action Television

• Greys Anatomy gave some of their doctors nicknames starting with Mc (as well as a few parodic ones), most prominently McDreamy and McSteamy.
• Happy Days: Fonzie sometimes uses the suffix "-amundo" for emphasis: correctamundo, exactamundo, etc. When he was a Rogue Juror he even voted "not guiltyamundo."
• Campier installments of the Batman franchise tend to prefix "bat" onto anything having to do with Batman. Examples include the phrase "same bat time, same bat channel", and the bat credit card.
• Saturday Night Live: Adam Sandler's Opera Man from the early 90's would sing his commentary in an exaggerated Italian accent by adding "a" or "o" to the end of many of his words. (An example (from Wikipedia): About the LA Riots - "La Chiefa Policia, no dispatcha gendarme/ morono, no respondo/ no excusa, bagga doucha!")
• Kenan And Kel: Throughout most of the first season, and some of the second, Chris had the habit of adding an extra preffix to his preterites, usually a "be" or "buh" sound, such as:
  "Kel, you be-bruised my bananas!"
  "How could you buh-lose a lottery ticket?"

Music

• Snoop Dogg attaches '-izzle' to a lot of his words, although a fair bit of those words have half of them removed, e.g. "fo' shizzle" for "for sure".

Video Games

• Final Fantasy X-2: According to Rikku's brother, Brother, she has a habit of doing this with human words, and even chides her for it. Most notably, her inclusion of, "iffic", to the word "disaster"; resulting in "disasteriffic".
• King Of Fighters: Yuri Sakazaki has a habit of ending nearly all of her sentences, and certain words, with "-tchi". It was originally a schtick her voice actress, Kaori Horie, came up with, which stuck and has since become a regular part of her character's speech pattern.

Western Animation

• Total Drama Island Season 4: Revenge of the Island had Lightning, whose big thing was words starting with "Sha-" (including Shazam).
• In Captain N The Game Master, Kid Icarus (who should have been named Pit) tended to tack "-icus" on the end of words.
• Due to the fact that he often speaks with a slight Speech Impediment (not unlike that of a 5-year-old), Mr Bogus will often use the word "mondo" before adding the letter 'o' at the end of a word used after it in his sentences. Examples include "Mondo coolo", "Mondo safe-o", etc.
• The Simpsons has two, by two different characters:
  • Homeric ma-infixation is an interesting application of McVocab in that the particle "-ma-" is an infix (it is put in the middle of a word), producing words like saxomaphone and babamabushka. Homer, as you can guess, uses it a lot.
  • Flanders also adds "-diddly" to a few of his words.
• Similar to the Homer Simpson example, Yogi Bear frequently calls picnic baskets "pic-a-nic baskets".

Other

• In Dwarf Fortress forums, it's fairly common for players to refer to their dwarves as "Urist Mc(adjective or profession)". As in "Urist McMiner", "Urist McSpeardwarf", or "Urist McCannonfodder".

Real Life

• McDonalds is the Trope Codifier for this, with their menu of 'Mc' foods. Soon everyone started doing it (although it is used to demonstrate how cheap or quickly-made something is), with words like 'McMansion' coming out of the woodwork.
  • Moscow On The Hudson character Vladimir does this when he works at McDonalds, to the point of making the parting statement to some customers, "Come back McSoon."

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