'dinornithiform' originates from New Latin 'Dinornithiformes', ultimately from Greek where 'deinos' meant 'terrible' and 'ornis/ornith-' meant 'bird', plus the Latin suffix '-form' meaning 'shape' or 'form'.

'dinornithiform' developed from the New Latin taxonomic name 'Dinornithiformes' (used for the moa order) and was adapted into English scientific usage as the adjective/noun 'dinornithiform'.

Initially used in strict taxonomic contexts to denote members of the order Dinornithiformes; over time it has also been used descriptively to mean 'resembling or relating to dinornithiforms'.