stief-

step-; a prefix indicating the individual being referred to is related through the marriage of a parent

Pronounced as (IPA)

/stif/

Etymology

Inherited from Middle Dutch: stief-

Inherited from Old Dutch: *stiop-

Cognate with German: stief-

Cognate with English: step-

Cognate with Middle Low German: stêf-

In summary

From Middle Dutch stief-, stiep-, from Old Dutch *stiop-, from Proto-West Germanic *steupa-, from Proto-Germanic *steupa- (“bereft, pushed out”).
Cognate with German stief-, English step-. The form with -f- arose through assimilation before the word vader (“father”); the generalization of this form may or may not have been reinforced by High German influence (where the -f- is regular). Compare the same in Middle Low German stêf-.