Curse that extra "h"!! Well, in true poet's fashion, I must declare this a new word. I'll say it's a noun, perhaps meaning the peek-a-boo move of an exotic dancer who wears only a thong. As in, "She fixed him with her sultry eyes, and did a little dipthong for his twenty." Building on that, I could change the initial "d" to a "t," and have it refer to the thong, itself. "He gingerly tucked his sweaty twenty into her tipthong."