'assessee' originates from English, specifically formed from the verb 'assess' plus the suffix '-ee' (borrowed via Anglo-French/French usage of agent/patient suffixes), where the verb 'assess' ultimately derives from Latin elements 'ad-' meaning 'to/toward' and 'sedēre' meaning 'to sit'.

'assessee' developed in English by combining the modern verb 'assess' (which entered English via Old French/Anglo-French from Latin roots) with the nominalizing suffix '-ee'; the verb 'assess' evolved from Latin (ad- + sedēre) through Old French forms into Middle English 'assessen' and then modern 'assess', after which the form 'assessee' was formed to denote the person being assessed.

Initially, the Latin root conveyed the idea 'to sit beside' (ad- + sedēre); over time the sense shifted to 'to evaluate or determine (value or tax liability)', and 'assessee' came to mean 'a person who is assessed' (especially for taxation or valuation).