'strap-like' is formed from the noun 'strap' and the suffix '-like'. 'strap' originates from Old Norse (or Old English) — Old Norse 'stropp' / Old English 'stræp' meaning 'a thong, strip, or band' — while the suffix '-like' comes from Old English 'lic' meaning 'body, form' (later developing the sense 'having the form of' or 'similar to').

'strap' entered Middle English as 'strappe' (from Old Norse/Old English roots) and became modern English 'strap'. The suffix '-like' derives from Old English 'lic' and developed into the Middle English formative '-like', giving adjectives meaning 'similar to' (e.g., 'childlike'); these elements combined to form compounds such as 'strap-like' in modern English.

Originally 'strap' referred specifically to a thong or narrow strip used for fastening, and '-like' (from 'lic') originally related to 'body' or 'form'; over time '-like' evolved to mean 'similar to' or 'having the characteristics of'. The compound 'strap-like' therefore came to mean 'resembling or having the qualities of a strap', which matches its current usage.