Source : Webster's Revised Unabridged Dictionary (1913)

Rhymer \Rhym"er\, n.
   One who makes rhymes; a versifier; -- generally in contempt;
   a poor poet; a poetaster.

         This would make them soon perceive what despicaple
         creatures our common rhymers and playwriters be.
                                                  --Milton.

Source : WordNet®

rhymer
     n : a writer who composes rhymes; a maker of poor verses
         (usually used as terms of contempt for minor or inferior
         poets) [syn: {rhymester}, {versifier}, {poetizer}, {poetiser}]