GNU Collaborative International Dictionary of English

Found one definition

1.       
   Looker (?), n.
   1. One who looks.
   
   [1913 Webster]
   
   
   2. A person who is physically very attractive, especially a beautiful woman.
   
   [PJC]
   
   Looker-on, a spectator; an onlooker; one that looks on, but has no agency or part in an affair.
   
   [1913 Webster]
   
   Did not this fatal war affront thy coast,
   
   Yet sattest thou an idle looker-on ? Fairfax.
   
   [1913 Webster]