Schmuck is most often used in American English as a pejorative or insult, meaning an obnoxious or contemptible person; one who is stupid, foolish, or detestable.
Variants of spelling and alterations include shmuck, schmo and shmo.
Schmuck entered English as a borrowed pejorative from the common Yiddish insult, where it is an obscene term for penis.[1] Its etymology is uncertain. In his cultural lexicon, The Joys of Yiddish, Leo Rosten lists the Yiddish schmuck as related to the Slovene word, ���¡mok, meaning "a fool, an innocent, a gullible dolt."[verification needed] The Online Etymology Dictionary derives it from the Polish word smok for dragon, as a euphemism for "penis".[2]