Alternative spelling of fight-or-flight

All the coordinated physiological responses that the sympathetic nervous system initiates in response to stress or other emergency situations.

(Internet slang, humorous) Used to request a picture of a reported event, especially on an Internet forum. / (Internet slang, humorous) Used to demand verifiable evidence for a statement.

If you don't have a lot of money, extend the life of what you have.

(idiomatic) At any time; 24/7

(idiomatic, set phrase) At this sole opportunity, or not at all.

A question suggesting sexual intercourse: literally meaning "shall we go to your place or mine to have sex?"

(sometimes proscribed) He or she; used as a gender-neutral reference to the third person singular.

plural of fill or kill

(stock market) A type of stock market or financial derivative order, signifying that the order is to be presented for execution, and if not executed ("filled") immediately (traditionally within a few seconds) is to be cancelled.