'autotoxin' originates from Greek-derived scientific elements: the prefix 'auto-' (from Greek 'autos') meaning 'self' and the word 'toxin' (from Greek 'toxikon') meaning 'poison'.

'autotoxin' was formed in modern scientific English by combining the Greek-derived prefix 'auto-' and the noun 'toxin'. The element 'toxin' itself comes from Greek 'toxikon' (related to 'toxon', 'bow/arrow'), which originally referred to an 'arrow-poison' and later generalized to 'poison'.

Initially the root 'toxin' referred broadly to 'poison' (originally an 'arrow poison'), but over time in scientific usage it came to mean specific poisonous substances; 'autotoxin' has evolved to mean specifically a poison produced by an organism that affects itself or its own species.