An archaic term possibly meaning a partner or companion, or humorously, a cuckolded partner whose spouse has been unfaithful.
Compound of 'cuckoo' (in the sense of a deceived person) + 'mate' (companion); the term appears sporadically in historical texts with varying definitions.
In Early Modern English, people created new insult words constantly by combining 'cuckoo' with other words to mock unfaithful relationships—cuckoomate is one of these creative but temporary slang terms that mostly disappeared.
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