'asperulous' originates from Latin, specifically the word 'asper', where 'asper' meant 'rough', combined with diminutive/adjectival elements to indicate 'somewhat rough'.

'asperulous' developed from Late Latin/Medieval Latin forms such as 'asperulosus' (formed from 'asper' + '-ulus' diminutive + '-osus' adjectival suffix) and was later adopted into English with the form 'asperulous'.

Initially it denoted 'somewhat rough' (a diminutive or attenuated sense of 'asper'), and it has retained that basic meaning of being mildly rough, with occasional figurative use for a harsh or rasping quality.