Anaphylaxic

Part of speech: adjective

Definitions

1. A severe, rapid allergic reaction that occurs when the body is exposed to a substance it has become sensitized to, characterized by symptoms such as difficulty breathing, swelling, and a sudden drop in blood pressure
2. relating to or causing a sudden, life-threatening allergic response involving immune system overreaction to an allergen
3. of or pertaining to an acute hypersensitivity reaction marked by respiratory distress, circulatory collapse, and systemic symptoms

Etymology: "Anaphylaxic" is an adjective formed from "anaphylaxis" with the adjectival suffix "-ic," so its meaning follows directly from the noun it is built on. The noun itself was coined in the early twentieth century from Greek roots: "ana," meaning "back" or "against," and "phylaxis," meaning "protection" or "guarding." The sense, then, is roughly "reverse protection," a name that reflects the surprising idea that the body's defensive response to a substance can itself cause harm. The adjective is the same word in a different grammatical role. Where "anaphylaxis" names the reaction, "anaphylaxic" describes something as belonging to or characteristic of it, as in an "anaphylaxic shock." The form is less common than the related "anaphylactic," which follows the Greek-based pattern more closely, so readers will encounter both spellings, though the two words share the same root and meaning.