'astronomer' originates from Greek, specifically the word 'astronomos', where 'astron' meant 'star' and 'nomos' meant 'law' or 'arrangement'.

'astronomos' changed into Latin 'astronomus' and Old French 'astronome', and eventually became the modern English word 'astronomer' through Middle English.

Initially, it meant 'one who studies or arranges the stars', but over time it evolved into its current meaning of 'a scientist who studies celestial objects and phenomena'.