'automysophobia' originates from Greek elements: 'autos' meaning 'self', 'mys' (from Greek 'mŷsos'/'muso-' related to dirt or filth) meaning 'dirt/filth', and 'phobia' from Greek 'phobos' meaning 'fear'.

'automysophobia' is a modern English coinage created by combining Greek roots ('autos' + 'mys' + 'phobia'); it was not a term in classical Greek but formed in modern usage to denote a fear of becoming dirty.

Formed in modern English to denote 'fear of dirt/contamination', it has come to be used specifically for an irrational fear of oneself becoming unclean.