'arccosine' originates from Modern English, specifically from the compound of 'arc' and 'cosine', where 'arc' comes from Latin 'arcus' meaning 'bow, curve' and 'cosine' ultimately derives from Latin 'cosinus' (via French), with the prefix 'co-' indicating 'complementary' and 'sinus' meaning 'curve or bend'.

'arccosine' developed from earlier mathematical formations such as 'arc-cosine' and the shortened notation 'arccos'; 'cosine' itself entered English from Latin 'cosinus' (through French) and ultimately from older mathematical terminology, leading to the modern English compound 'arccosine'.

Initially the elements referred to 'an arc related to the complementary sine', but over time the compound came to denote specifically the inverse function of the cosine, i.e., the angle corresponding to a given cosine value.