Learner's definition of WIT
an ability to say or write things that are clever and usually funny
She is full of wit and vivacity.
His latest book doesn't have the same wit as his earlier books.
The book is a collection of his wit and wisdom.
a person who is known for making clever and funny remarks
see also half-wit, nitwit
the ability to think or reason
see also battle of wits at 1battle
She's got the wits [=intelligence] to make it work.
He learned to live by his wits. [=to survive by doing clever and sometimes dishonest things]
She can keep her wits about her [=remain calm and able to think clearly] in a crisis.
He needed a moment to gather/collect his wits [=to become calm and able to think clearly] after the collision.
(chiefly US) The chess champion will match wits [=compete] with a computer. = (chiefly Brit) He will pit his wits against a computer.
the ability to make good decisions
at (your) wit's end
at (your) wits' end
not able to continue thinking or trying to solve a problem
upset and unable to think of what needs to be done
I've spent six hours trying to fix my computer, but now I'm at my wit's end.
She's at her wit's end trying to keep her brother out of trouble.
out of your wits
— used for emphasis with verbs like scare and frighten
— used before stating the specific thing or example being discussed