stepyoudaoicibaDictYouDict[step 词源字典]
step: [OE] Step, together with its relatives German stapfen and Dutch steppen, comes from a prehistoric West Germanic base *stap- ‘tread’ (a nasalized version of which produced English stamp). (Russian step, source of English steppe [17], is not related.) The prefix step- [OE], as in stepdaughter, stepfather, etc, originated in a word meaning ‘orphan’. It is related to Old High German stiufen ‘bereave’.
=> stamp[step etymology, step origin, 英语词源]