'ankylosaurus' originates from New Latin, specifically the word 'Ankylosaurus', where the elements 'ankyl-' came from Greek 'ankylos' meaning 'bent, fused' and 'sauros' meant 'lizard'.

'ankylosaurus' was formed in Neo-Latin from Greek roots 'ankylos' + 'sauros' and was adopted into modern English scientific nomenclature as the genus name 'Ankylosaurus'.

Initially it literally meant 'fused (or bent) lizard' referring to fused dermal bones; over time it became the proper name for the specific armored dinosaur genus Ankylosaurus.