Deterrer

Part of speech: noun

Definitions

1. To prevent someone from doing something by instilling doubt or fear
2. To discourage an action or behavior through threats or consequences
3. To inhibit an individual from proceeding by creating barriers to their intent

Etymology: Latin "dēterrēre" meant "to frighten away from," built from "dē-" ("away, down") and "terrēre" ("to frighten"), the same root that gives English "terror." The sense was literal: to scare someone off a course of action, not to persuade them against it. English took the stem as "deter," which kept that frightening core. "Deterrer" is simply "deter" with the English suffix "-er," which marks someone or something that does the action. That suffix has a long route: it descends from Old English "-ere," and its ultimate source is the Latin "-ārius," which passed through Old French "-ier" before reaching Middle English. Each step left the suffix's meaning of "one who does" intact.

Synonyms: preventer, dissuader, discourager, obstructor, impeder