What is Wit?
Wit is (noun) 1. an ability to say clever and funny things His wit comes out all through his book. 2. at your wits’ end not knowing what to do next They were at their wits’ end when the builders reported even more structural problems in the house. to keep your wits about you to keep calm in a difficult situation and think hard what to do next Don’t panic, keep your wits about you, and everything will be all right.
source: Easier English, Student Dictionary Upper Intermediate Level