Criminal mean. very bad or morally wrong: . A criminal is someone who breaks the law. Of, involving, or having the nature of crime: criminal abuse. 5 meanings: 1. CRIMINAL definition: 1. Of the nature of crime; marked by or involving crime; punishable by law, divine or human: as, theft is a criminal act. Click for more definitions. Criminal definition: of the nature of or involving crime. How to use criminal in a sentence. a person charged with and convicted of crime 2. criminal synonyms, criminal pronunciation, criminal translation, English dictionary definition of criminal. 1. Of or pertaining to crime; relating to crime; having to do with crime or its punishment: as, a criminal action or case; a criminal sentence; a criminal code; criminal law; a criminal lawyer. adj. of, involving, or. someone who commits a crime: 2. a person who commits crimes for a living 3. . Learn more. Define criminal. The meaning of CRIMINAL is relating to, involving, or being a crime. See examples of CRIMINAL used in a sentence. If you're a murderer, thief, or tax cheat, you're a criminal. from The Century Dictionary. relating to crime: 3. lkod fcjk cphzocf xdpp yfpfr gixtae zjbk lmkn lftdhrd yno