'triol' originates from the International scientific vocabulary, combining the prefix 'tri-' (from Greek 'treis') meaning 'three' and the suffix '-ol' (from 'alcohol', ultimately Arabic 'al-kuhl') used to denote alcohols.

'triol' was formed in the 19th century by joining 'tri-' + '-ol' as part of systematic chemical naming; it appears in chemical literature as 'triol' and has been used to name alcohols with three hydroxyl groups since then.

Initially, it meant 'an alcohol containing three hydroxyl groups', and this core meaning has largely remained the same in modern usage.