'antiodontalgic' originates from Greek elements: the prefix 'anti-' meaning 'against' and the root from 'odontalgia' ('odonto-' from Greek 'odous/odont-' meaning 'tooth' and 'algos/algia' meaning 'pain').

'antiodontalgic' was formed in modern English by combining the productive prefix 'anti-' with the medical noun 'odontalgia' (from Greek 'odónt-' + 'álgos'); the element produced terms such as 'odontalgia' and 'odontalgic' in medical usage, and later 'antiodontalgic' appeared as a compound meaning 'against toothache'.

Initially the relevant roots described 'tooth' and 'pain' separately, but in modern compound usage they evolved to denote 'relieving or opposing toothache,' which is the current meaning of 'antiodontalgic'.