"having an allergy (to something)," 1911, from allergy (q.v.) + -ic; perhaps modeled on French allergique (1906). The figurative use, "antipathetic, repulsed" is by 1936.
Entries linking to allergic
allergy n.
"condition caused by hypersensitivity of the immune system to typically harmless substances," 1911, from German Allergie, coined 1906 by Austrian pediatrician Clemens E. von Pirquet (1874-1929) as an abstract noun from Greek allos "other, different, strange" (from PIE root *al- (1) "beyond") + ergon "work, activity" (from PIE root *werg- "to do").
-ic
Middle English -ik, -ick, word-forming element making adjectives, "having to do with, having the nature of, being, made of, caused by, similar to," from French -ique and directly from Latin -icus or from cognate Greek -ikos "in the manner of; pertaining to." From PIE adjective suffix *-(i)ko, which also yielded Slavic -isku, adjectival suffix indicating origin, the source of the -sky (Russian -skii) in many surnames. In chemistry, indicating a higher valence than names in -ous (first in benzoic, 1791).
In Middle English and after often spelled -ick, -ike, -ique. Variant forms in -ick (critick, ethick) were common in early Modern English and survived in English dictionaries into early 19c. This spelling was supported by Johnson but opposed by Webster, who prevailed.
*werg-
Proto-Indo-European root meaning "to do."
It forms all or part of: allergic; allergy; argon; boulevard; bulwark; cholinergic; demiurge; dramaturge; energy; erg (n.1) "unit of energy;" ergative; ergonomics; ergophobia; George; georgic; handiwork; irk; lethargic; lethargy; liturgy; metallurgy; organ; organelle; organic; organism; organize; orgy; surgeon; surgery; synergism; synergy; thaumaturge; work; wright; wrought; zymurgy.
It is the hypothetical source of/evidence for its existence is provided by: Greek ergon "work," orgia "religious performances;" Armenian gorc "work;" Avestan vareza "work, activity;" Gothic waurkjan, Old English wyrcan "to work," Old English weorc "deed, action, something done;" Old Norse yrka "work, take effect."