'weed-resistant' is a compound of 'weed' and 'resistant'. 'weed' originates from Old English 'wēod' meaning 'herb, weed', and 'resistant' comes from Latin 'resistere' (via Old French and Middle English) meaning 'to stand back or oppose'.

'resistere' in Latin developed into Old French forms (e.g. 'resister') and entered Middle English as 'resist', later yielding the adjective 'resistant'. 'weed' derives from Old English 'wēod' and retained the meaning of 'herb' or 'unwanted plant'; the compound 'weed-resistant' is a modern English formation combining these elements.

Initially the elements meant 'weed' (a herb or unwanted plant) and 'to resist' (to stand against); combined in modern usage they specifically describe something that resists the growth or invasion of weeds.