soul mate /ˈsōl ˌmāt/ noun noun: soulmate a person ideally suited to another as a close friend or romantic partner. Soulmate A soulmate is a person with whom one has a feeling of deep or natural affinity. This may involve similarity, love, romance, platonic relationships, comfort, intimacy, spirituality, compatibility and trust. The more we pass each other by, the more we sync up.