a tall cupboard or wardrobe with a door, used for storage

he has a closet full of designer suits

used to refer to a state of secrecy or concealment, especially about one's homosexuality

his brother's decision to come out of the closet

she tries to have a relationship with another woman while remaining in the closet

secret; covert

a closet smoker

shut (someone) away, especially in private conference or study

he was closeted with the king

he returned home and closeted himself in his room