1.
You say not a ~ or not one ~ to emphasize that something is not the case at all. (mainly FORMAL or OLD-FASHIONED)
He cared not a ~ for the social, political or moral aspects of literature...
PHRASE: with neg, PHR after v emphasis
2.
Whit means the same as Whitsun .
The orchestra gave its first performance on Whit Monday.
N-UNCOUNT: usu N n