'Commons' ultimately originates from Latin, specifically the word 'communis' meaning 'shared, common', which passed into Old French as 'commun' and then into Middle English.

'Commons' developed from Middle English 'communs' (plural) and from the adjective 'common' (from Old French 'commun' and Latin 'communis'); the plural form came to be used as a noun for shared lands and later for the assembly ('the Commons').

Initially it referred to 'things held in common' or 'shared lands'; over time it extended to mean collective resources generally and to denote the elected assembly of commoners (the House of Commons).