Malimar
People complain about "reversing the polarity of the neutron flow" being meaningless because neutrons have no polarity. But the Doctor never reversed the polarity of the neutrons themselves; he reversed the polarity of the flow. Other than alternating current, all flows have polarity.
Moreover, even if the word "flow" weren't in there, reversing the polarity of something that actually has polarity could be even worse. At least reversing the polarity of neutrons does nothing. Reversing the polarity of electrons or protons (i.e., turning them into positrons or antiprotons, respectively) would cause them to annihilate with the surrounding matter, killing everyone.
Deleted the following from the Star Trek The Next Generation example because it isn't actually reversing anything.
"Geordi could make the Enterprise do anything by "routing (some piece of Techno Babble) through the main deflector array"."
Also moved the Star Trek Generations example to the Film section.
Edited by Arivne
The Doctor has said the full phrase twice. In "The Sea Devils" and "The Five Doctors".