1. (verb)carbon black, lampblack, soot, smut, crock a black colloidal substance consisting wholly or principally of amorphous carbon and used to make pigments and ink Synonyms: soot, filth, obscenity, smut fungus, dirty word, porn, crock, erotica, earthenware jar, vulgarism, lampblack, smut, carbon black, pornography, porno