Tiptoe means to walk quietly and carefully with your heels raised and your weight placed on the balls of your feet.(verb)
When you are quietly sneaking in after curfew and you tread lightly, walking with your weight on the front of your feet and your heels in the air, this is an example of when you tiptoe.
See tiptoe in Webster's New World College Dictionary
See tiptoe in American Heritage Dictionary 4
intransitive verb tip·toed, tip·toe·ing, tip·toes
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