In social relationships, an
ex (plural is
exes) is someone with whom a person was once associated in a relationship or marriage. As a
prefix,
ex- can refer to a variety of different
relationships; for example, one might refer to a music group's
ex-guitarist, or someone's
ex-friend. When used alone,
ex as a noun is assumed to refer to a former sexual or romantic partner, especially a
former spouse. This often has a derogatory tinge, especially if it refers to unrequited feelings.