Past it is an informal term used to describe someone or something that is no longer able to function at the same level as before due to age or obsolescence. There are several synonyms for past it, including outdated, obsolete, antiquated, old-fashioned, outmoded, out-of-date, and passe. These words refer to things that are no longer relevant or useful, either because they have been replaced by newer and better alternatives or because they are simply too old and worn out. Synonyms for past it can be used to describe anything from a piece of technology to a person who is no longer able to keep up with modern trends or ideas.