The Double dactyl reference article from the English Wikipedia on 24-Apr-2004
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Double dactyl

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A dactyl is a poetic foot of the form >-- (ON-off-off). For example, interstate, realize, microphone, cereal, limerick, etc. etc. A double dactyl is two dactyls in a row.

A double dactyl is also a poem. Like a limerick, it has a rigid structure. Two stanzas, each comprising three lines of dactylic dimeter followed by a line with a dactyl and a single accent. The two stanzas have to rhyme on their last line. The first line of the first stanza is repetitive nonsense. The second line of the first stanza is somebody's name -- strictly speaking, a proper noun. Note that this name must itself be double-dactylic.