Is it ensure, insure, or assure?
to leave quickly
a type of jet ski; generally, a motorized toboggan; also written Skidoo
a vogue word of 1905, "to leave in a hurry," perhaps a variant of skedaddle (q.v.). The association with twenty-three is as old as the word, but the exact connection is obscure.
Then skidoo, little girl, skidoo.
23 is the number for you.
A motorcyclist's helmet: suffered severe brain damage while wearing one of the company's skid lids (1970s+ Motorcyclists)