'canonicity' originates from Late Latin, specifically the word 'canonicus', where 'canonicus' related to 'of the rule' derived from Greek 'kanon' meaning 'rule' or 'measuring rod'.

'canonicity' developed via Late Latin 'canonicus' and Medieval Latin forms into Middle English (through Old French/Latin influences) and eventually became the modern English noun 'canonicity' (formed from 'canonical' + '-ity').

Initially it referred to relation to a 'rule' or 'norm' (from 'kanon'); over time it narrowed to mean specifically the status of being part of an accepted canon or authoritative collection (e.g., canonical texts).