Source : Webster's Revised Unabridged Dictionary (1913)

Greenish \Green"ish\, a.
   Somewhat green; having a tinge of green; as, a greenish
   yellow. -- {Green"ish*ness}, n.

Source : WordNet®

greenish
     adj : similar to the color of fresh grass; "a green tree"; "green
           fields"; "green paint" [syn: {green}, {light-green}, {dark-green}]