What does the phrase 'can it' mean?

Answer:
It means, "put it in the (trash) can" -- usually figuratively, not literally.

It means put an end to it, stop it.
discard it and begin again

I always thought it meant to shut up.
First answer by ID2256080349. Last edit by Napalmcheng. Contributor trust: 18 [recommend contributor recommended]. Question popularity: 7 [recommend question].