Lifer, e.g. is a term used to describe someone who has been sentenced to life in prison without the possibility of parole. The crossword solutions for this term are FELON (5 letters), CON (3 letters), and INMATE (6 letters). A FELON is someone who has committed a serious crime such as murder, rape, or robbery. A CON is a person who engages in fraud or deceit. An INMATE is someone who is confined to a prison or other institution such as a mental hospital.