stiff
n. countablen. a person who is boring, very formal, or lacks a sense of humor. It is also a very casual and slightly disrespectful way to talk about a dead body.
n. a person who is excessively formal, conventional, or socially awkward; in a separate informal register, a corpse. The term is often used pejoratively to describe someone who lacks spontaneity.
Don't be such a stiff and come dance with us.
The party was full of corporate stiffs in grey suits who only wanted to talk about their quarterly earnings.
While the detective was used to dealing with a stiff at a crime scene, he found the bureaucratic stiffs at headquarters much harder to manage.
From Middle English stiff, stiffe, stif, from Old English stīf, from Proto-West Germanic stīf, from Proto-Germanic stīfaz, from Proto-Indo-European *steypós. See also West Frisian stiif, Dutch stijf, Norwegian Bokmål stiv, German steif; also Latin stīpes, stīpō, from which English stevedore. The expected Modern English form would be /staɪf/; /stɪf/ is probably originally from compounds such as stiffly, where the vowel was shortened before a consonant cluster.