clerihew

from WordNet (r) 3.0 (2006)

clerihew
    n 1: a witty satiric verse containing two rhymed couplets and
         mentioning a famous person; "`The president is George W.
         Bush, Who is happy to sit on his tush, While sending his
         armies to fight, For anything he thinks is right' is a
         clerihew"

from The Collaborative International Dictionary of English v.0.48

clerihew \clerihew\ n.
   a witty satiric verse containing two rhymed couplets and
   mentioning a famous person.
   [WordNet 1.5]