The word 'strap' entered English in the 14th century from Old French, carrying the sense of a band or loop used for binding or securing. Its ultimate origin is traced to a Proto-Germanic root, likely related to words meaning "to turn" or "to twist," which is evident in its Dutch and German cognates referring to loops and nooses. This etymological journey from a concept of a twisted loop or snare evolved logically into the modern meaning of a flat, flexible band designed for fastening or holding objects securely. The core idea of a constraining or securing band has remained consistent throughout its linguistic history.

The word 'strap' is a simplex word. It is a loanword from Old French 'estrap' or 'estrappe', meaning "a trap, snare; strap or strop for an oar," which itself likely came from a Low German source (e.g., Middle Dutch 'strop' meaning "noose, band").