"Be in stir" is an idiom that refers to being in prison or jail. There are various synonyms for this expression, including being locked up, incarcerated, imprisoned, detained, or held in custody. Each of these words emphasizes the lack of freedom and confinement that comes with being behind bars. Another synonym that highlights the idea of punishment is being punished or penalized. Some slang synonyms for "be in stir" include being in the can, the joint, the slammer, or the clink. Regardless of the words used, being in stir is a serious consequence of breaking the law and can have far-reaching implications for an individual's life.