blowjob (plural blowjobs) (vulgar, slang) An act of fellatio, or sucking a penis or other phallic object (such as a dildo). [from 1942][1] synonym Synonyms: see Thesaurus: oral sex (figurative, derogatory) Excessive praise. Oral sex means a person receives stimulation from their partner’s mouth. Learn more about how to discuss oral sex with your partner and stay safe. Definition of ' blow job ' blow job in British English noun a vulgar slang term for fellatio Blow job definition : an act or instance of fellatio.. See examples of BLOW JOB used in a sentence.