'selfing' originates from English, specifically formed from the word 'self' with the suffix '-ing', where 'self' meant 'one's own' (from Old English 'seolf') and '-ing' meant 'action, process, or result.'

'selfing' developed from Old English 'seolf'/'self' combined with the grammatical '-ing' ending in Middle English; the compound 'self' + '-ing' eventually produced the modern term 'selfing', later adopted as a technical term in biology.

Initially, the element 'self' primarily meant 'one's own' or 'by oneself'; over time 'selfing' evolved to refer specifically to the biological process of self-fertilization.