'trichome' originates from Greek, specifically the word 'trichōma' (Ancient Greek τρίχωμα), where 'trich-' meant 'hair' and '-ōma' (or '-oma') meant 'a growth or tumor'.

'trichome' passed into New Latin as 'trichoma' (used in botanical and medical contexts) and was later borrowed into English in the 19th century as 'trichome'.

Initially it referred generally to 'a hairy growth' (sometimes with medical connotations like a tumor); over time it became specialized in botanical usage to mean 'a hairlike outgrowth on plant epidermis, often with protective or secretory functions'.