allergenic

the term 'allergenic' is a modern scientific construction built upon the 20th-century medical word 'allergy'. the base 'allerg' is a clipped form of 'allergy', which itself was coined in 1906 by austrian pediatrician clemens von pirquet from the greek roots allos (other, different) and ergon (work, activity), to describe an altered or unusual bodily reaction. the suffixes '-en-' and '-ic' are classic adjectival formants from greek and latin, layered onto this modern base to create a word that specifically means 'pertaining to or characterized by causing an allergic reaction'. thus, the word's logic moves from the ancient concept of 'other work' to the modern medical concept of hypersensitivity, with 'allergenic' precisely describing the causative agent of that condition.