What is the origin of atiptoe?
If children wait atiptoe for Christmas morning, they are “eagerly expectant,” their anticipation likened to the excitement associated with standing on tiptoe. And indeed, “on tiptoe” is what the adjective and adverb atiptoe literally means. The initial a– in atiptoe is a reduced form of the Old English preposition on, variously meaning “on, in, into, toward.” This particular a– (the form has many other senses or functions in English) appears in a great variety of words, such as acknowledge, ablaze, aloud, and away. So, afoot, as another example, began as the prepositional phrase on foot. Atiptoe is recorded English by the late 1500s.