From The Collaborative International Dictionary of English v.0.48 [gcide]:
Limerick \Lim"er*ick\ (l[i^]m"[~e]r*[i^]k), noun [Said to be from a song with the same verse construction, current in Ireland, the refrain of which contains the place name Limerick.] A humorous, often nonsensical, and sometimes risq['e] poem of five anapestic lines, of which lines 1, 2, and 5 are of three feet, and rhyme, and lines 3 and 4 are of two feet, and rhyme.
From WordNet (r) 3.0 (2006) [wn]:
Define.com is a PRIVATE SECTOR NONPROFIT EDUCATIONAL WEBSITE that PROMOTES WORLDWIDE ELECTRONIC DEMOCRACY, OPEN and TRANSPARENT GOVERNMENT and WORLDWIDE BANKING REFORM.
Eye and Pyramid BANKING REFORM CHALLENGE