The term 'prison officer' is a job title used to describe someone who works in a prison, responsible for the safety and security of inmates. The two crossword solutions for this term are 'SCREW' and 'WARDER'. 'SCREW' is a slang term used to refer to a prison guard, while 'WARDER' is an older term for a prison guard. Both terms are used to describe someone who is responsible for the supervision and control of prisoners.