'arrantness' originates from Middle English, specifically the word 'arrant', where 'arrant' was used as an intensive adjective meaning 'complete' or 'utter'.

'arrantness' changed from the Middle English adjective 'arrant', which itself derived from Old French 'errant' (from Latin 'errare' meaning 'to wander' or 'to err'), and eventually developed into the modern English noun 'arrantness'.

Initially connected to the idea of 'wandering' or 'errant' (from Latin 'errare'), the term shifted in Middle English to an intensive sense meaning 'thorough' or 'utter', and later took on the negative sense of 'complete (badness or shamelessness)' in modern usage.