At a (fair) lick British phrase informal
The word "fair" can be replaced by "great" without changing the meaning.
At a high speed
The car started going at a lick when it entered the highway.
The cheetah runs at a fair lick when chasing the prey.
In comic books, Superman can do everything at a great lick.
Very quick
Extremely fast as if having been abruptly startled or shocked
To move or work something at a faster pace
Used to refer to someone or something moves or works at very high speed
If he or she does something at his or her own pace, he or she does it at the ideal speed for himself or herself.