step-

Meaning

A prefix used before father, mother, brother, sister, son, daughter, child, and so forth, to indicate that the person being identified is not a blood relative but is related through the marriage of a parent.

Synonyms

foster

Etymology

Inherited from Middle English: step-

Inherited from Old English: stēop-

Cognate with Scots: step-

Cognate with Western Frisian: stiep-

Cognate with Dutch: stief-

Cognate with Low German: steef-

Cognate with German: stief-

Cognate with Swedish: styv-

Cognate with Icelandic: stjúp-

Cognate with Old English: stīepan

In summary

From Middle English step-, from Old English stēop- (“deprived of a relative, step-”, prefix), from Proto-West Germanic *steupa-, from Proto-Germanic *steupa- (“orphaned, step-”), from Proto-Indo-European *(s)tewp- (“to push, strike”).
Cognate with Scots step- (“step-”), West Frisian stiep- (“step-”), Dutch stief- (“step-”), Low German steef- (“step-”), German stief- (“step-”), Swedish styv- (“step-”), Icelandic stjúp- (“step-”). Related to Old English stīepan (“to deprive, bereave”). Not, however, related to the familiar English noun or verb step.