That little part of your brain that will hear or think of something hilarious but inappropriate, which will act as its ignition. It is then powered by your attempts to ignore it, and will accelerate, never reaching a terminal speed and only stopping when you blurt out whatever thought started it at the worst possible moment. It is related - but not linked to - that part of your brain that inexorably broadcasts horrific images to the rest of your brain at inconvenient times, for example: images of corpses while eating, images of your mum during sex etc.

Called 'man motor' because there is no evidence of this phenomenon ever occurring in females.
Your idiot thoughts during a funeral: Hey, that dude who was killed in a horrific car accident at the age of 25's wife's face kinda looks like a pan-fried vagina.

Man motor: *click! whirr...* Yep, pan-fried vagina. Probably should tell someone that.

That one part of your brain responsible for - and completely incapable of - inhibition: No, that's horrible.

Man Motor: *Whirrrrrrrrrrrr...* Nah, go on, it'll be funny. You love causing egregious grief.

Inhibition: No, Man Motor, no.

Man Motor *WHHIIRRRRRRRR...* Come on, you don't know how people will react, they might like it.

Inhibition: Please stop trying to-

Man Motor: *WWWHHHHHIIIIIRRRRRRRRRRR...* PAN-FRIED VAGINA PAN-FRIED VAGINA PAN-FRIED VAGINA

You: HEY, DEAD MAN'S WIFE, YOU LOOK LIKE A PAN-FRIED VAGINA!

Everyone: *mortified gasps*

You, at the behest of your Man Motor: So... Anyone wanna fuck?
by Josh Turnbull June 7, 2010
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Someone you might leave home to meet.
Waiting to keep the appointment she made
Meeting a man from the motor trade
by H. Douglas Nuts December 20, 2007
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Usually a middle-aged man with an Alabama hat, sunglasses, and a beer in his hand who takes everything to another level and talks about boats even though they only have a 2001 red motorboat that can hold only 2 people.
My dad, uncle, other uncle, teacher, therapist, and every other middle-aged man I know is a motor man.
by Yourbirthmamalmeao December 8, 2021
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