'archlecher' originates from a combination of the prefix 'arch-' and the noun 'lecher'. 'arch-' ultimately comes from Greek, specifically the element 'arkhós'/'arkhē' where 'arkh-' meant 'chief, principal', and 'lecher' comes from Old English/Old French roots ('lǣċere' / 'lecheor') meaning 'one given to lechery'.

'archlecher' was formed in English by prefixing 'arch-' (used as an intensifier meaning 'extreme' or 'principal') to the existing Middle English word 'lecher' (from Old French 'lecheor' / Old English 'lǣċere'), producing the compound 'archlecher' now found in archaic or literary usage.

Initially, it carried the literal sense 'chief or extreme lecher'; over time the meaning has remained largely the same but the word has become rare and archaic, often used for emphatic or literary effect.