The Collaborative International Dictionary of English v.0.48:

Reddish \Red"dish\ (r?d"d?sh), a.
   Somewhat red; moderately red. -- Red"dish*ness, n.
   [1913 Webster]

WordNet (r) 3.0 (2006):

reddish
    adj 1: of a color at the end of the color spectrum (next to
           orange); resembling the color of blood or cherries or
           tomatoes or rubies [syn: red, reddish, ruddy,
           blood-red, carmine, cerise, cherry, cherry-red,
           crimson, ruby, ruby-red, scarlet]