'areometer' originates from French, specifically the word 'aréomètre', where 'aré(o)-' ultimately comes from Greek 'araios' meaning 'thin' and '-meter' from Greek 'metron' meaning 'measure'.

'areometer' changed from French 'aréomètre' and New Latin 'areometrum' and eventually became the modern English word 'areometer'.

Initially, it meant 'an instrument for measuring thinness', but over time it evolved into its current meaning of 'an instrument for measuring density (specific gravity) of liquids'.