1
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Dance, as in Let's go out tonight and trip the light fantastic. This expression was originated by John Milton in L'Allegro (1632): "Come and trip it as ye go, On the light fantastick toe." The idiom uses trip in the sense of "a light, tripping step," and although fantastick was never the name of any particular dance, it survived and was given revived currency in James W. Blake's immensely popular song, The Sidewalks of New York (1894).
American Heritage Idioms
2
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Phrase(s): trip the light fantastic
Jocular to dance. • Shall we go trip the light fantastic?
McGrawhill's American Idioms And Phrasal Verbs