'isogamy' originates from Greek, specifically the elements 'isos' meaning 'equal' and 'gamos' meaning 'marriage' or 'union'.

'isogamy' entered scientific usage via New Latin/Modern Latin (e.g. 'isogamia') formed from Greek roots and was adopted into English with the sense relating to similarity of gametes in biology.

Initially constructed from roots meaning 'equal marriage/union,' the term evolved into a technical biological term meaning 'reproduction by equal (or similar) gametes.'