What is "to hit on"

Hit \Hit\, v. i.

1. To meet or come in contact; to strike; to clash; -- followed by against or on.

   If bodies be extension alone, how can they move and hit one against another?
   --Locke.

   Corpuscles, meeting with or hitting on those bodies, become conjoined with them.
   --Woodward.

2. To meet or reach what was aimed at or desired; to succeed, -- often with implied chance, or luck.

   And oft it hits Where hope is coldest and despair most fits.
   --Shak.

   And millions miss for one that hits.
   --Swift.

   To hit on or To hit upon, to light upon; to come to by chance; to discover unexpectedly; as, he hit on the solution after days of trying. ``None of them hit upon the art.''
   --Addison.