'adnumber' originates from the combination of 'ad' (short for 'advertisement') and 'number', where 'ad' refers to a public promotion of a product or service, and 'number' refers to a numerical identifier.

'adnumber' is a modern term that combines 'ad' and 'number' to create a new word used in marketing and advertising contexts.

Initially, it meant a numerical identifier for advertisements, and this meaning has remained consistent in modern usage.