'ankylo-' originates from Greek, specifically the word 'ankylos', where 'ankyl-' meant 'bent, crooked, stiff'.

'ankylos' passed into Late/Medieval Latin and New Latin as forms such as 'ankylose'/'ankylosis' and ultimately entered English medical vocabulary as 'ankylosis' and the combining form 'ankylo-'.

Initially it meant 'curved or bent', but over time, especially in medical usage, it evolved to denote 'stiffness or fusion' (notably of bones or joints).