IN ONCE, phr. (common).First time.
 
  1900.  G. R. SIMS, In Londons Heart, 72. Meaning, Jim, he said 
 you found something in the cab as is of a private natur? Youve guessed it IN ONCE, father.
 
  1900.  Free Lance, 6 Oct., 16, 1. Youve hit it IN ONCE.