A limerick is a rhyming poem or a humorous song.
While under the influence of the polywater intoxication in 2364, an officer aboard the USS Enterprise-D delivered a peculiar limerick about a woman from Venus while in the shuttlecraft bay. (TNG: "The Naked Now")
Michael Sullivan, while discussed the topic of poetry with Kathryn Janeway, noted how much Jane Eldon and Sean Gogerty shared similar rhyming schemes. Janeway was, however, not familiar with either poet, and was told by Sullivan that she had some catching up to do, and invited her to join him sometime. Sullivan further explained the one time he tried talking poetry with Seamus, but that "all he can do is recite limericks." (VOY: "Fair Haven")
In 2376, Harry Kim considered tweaking Tuvok's holo-program of the Temple of T'Panit, so that instead of Vulcan prayers, the monks recite Ferengi limericks, in attempt to make Tuvok laugh. He shared this thought with Lyndsay Ballard, but her mind was elsewhere. (VOY: "Ashes to Ashes")