'allergist' originates from the Greek word 'allergia,' where 'allos' meant 'other' and 'ergon' meant 'work.'

'allergia' transformed into the French word 'allergie,' and eventually became the modern English word 'allergy,' from which 'allergist' is derived.

Initially, it meant 'a reaction to foreign substances,' but over time it evolved into its current meaning of 'a specialist in allergies.'