From Longman Dictionary of Contemporary Englishliferlif‧er /ˈlaɪfə $ -ər/ noun [countable] informalSCJPUNISH someone who has been sent to prison for the rest of their life
Examples from the Corpus
lifer• At least a lifer, Holmes.• Effectively, their friendship had ended when Converse was discharged and Hicks became, as he thought, a lifer.• Sometimes we get sent to fetch lifers to come over to our side.• I don't know how lifers cope with it, but they do.• Sometimes it's so they can moon around and say how beautiful it all was and pretend they're still lifers there.• It must be Government policy to give the lifer some dignity.• He was like the rest of the lifers, he didn't need me any more.• IBMers are typically lifers IBMers are typically lifers.