Tiptoe

来自Big Physics

wiktionary

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tip +‎  toe


etymonline

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tiptoe (n.)

late 14c., from tip (n.1) + toe (n.). As an adverb from 1590s; as a verb from 1630s. Related: Tiptoes (late 14c.), also tiptoon; tip-toed. Tippy-toes is from 1820.