cogency

the word "cogency" originates from the latin verb cogere, meaning "to drive together" or "to compel." this verb itself is a compound of co- (an intensifying prefix meaning "together") and agere (a fundamental verb meaning "to drive, set in motion, or do"). the semantic journey moved from the physical act of herding or compelling objects into one place, to the mental act of compelling thoughts or arguments into a coherent, forceful whole. the suffix -entia was added to form the abstract noun cogentia, denoting the quality of being compelling. entering english in the 17th century, "cogency" retained this core sense, now specifically describing the compelling power of logic, evidence, or reasoning that drives conviction in the mind of a listener or reader.

Structure: cog (drive, think) + ency (noun suffix) cog: from latin cogere ("to drive together, compel, force"), from co- (together) + agere (to drive, do, act). in this word, it functions as the core root conveying the sense of driving or compelling force. ency: a noun-forming suffix of latin origin (-entia), indicating a state, quality, or condition.