The Collaborative International Dictionary of English v.0.48:

Liken \Lik"en\ (l[imac]k"'n), v. t. [imp. & p. p. Likened
   (l[imac]k"'nd); p. pr. & vb. n. Likening.] [OE. liknen. See
   Like, a.]
   1. To allege, or think, to be like; to represent as like; to
      compare; as, to liken life to a pilgrimage.
      [1913 Webster]

            Whosoever heareth these sayings of mine, and doeth
            them, I will liken him unto a wise man which built
            his house upon a rock.                --Matt. vii.
                                                  24.
      [1913 Webster]

   2. To make or cause to be like. [R.] --Brougham.
      [1913 Webster]

WordNet (r) 3.0 (2006):

liken
    v 1: consider or describe as similar, equal, or analogous; "We
         can compare the Han dynasty to the Romans"; "You cannot
         equate success in financial matters with greed" [syn:
         compare, liken, equate]

Moby Thesaurus II by Grady Ward, 1.0:

33 Moby Thesaurus words for "liken":
   analogize, assimilate, balance, bring into analogy,
   bring into comparison, compare, compare and contrast, compare with,
   confront, contrast, counterpose, draw a comparison,
   draw a parallel, equate, juxtapose, liken to, match,
   measure against, metaphorize, oppose, paragon, parallel,
   place against, relate, run a comparison, set in contrast,
   set in opposition, set off against, set over against, similize,
   view together, weigh, weigh against