'prosimian' originates from New Latin, specifically the word 'Prosimia', where the prefix 'pro-' meant 'before' and Latin 'simia' meant 'ape'.

'prosimian' changed from the New Latin word 'Prosimia' and was adopted into English in the 19th century as 'prosimian' to refer to the group of 'pre-apes' (primitive primates).

Initially, it meant 'before apes' (i.e., animals preceding or more primitive than apes), but over time it evolved into its current meaning of 'a group of primates including lemurs, lorises, galagos, and sometimes tarsiers'.