bedmate is a compound of bed + mate. Mate is from Middle Low German māt(e) ('comrade, messmate'), literally 'one who eats at the same table', from Proto-Germanic *gamatô. Morphologically, the word is transparent as a compound: its parts remain visible in the modern spelling, while the older history of those parts supplies the deeper ancestry. In modern use, the noun sense is "a person with whom one shares a bed", which keeps the etymology connected to the word's present dictionary value rather than treating it as a merely historical label. The wider word family includes related English forms such as bed, mate, showing how the same base continues to support neighboring English vocabulary. The principal historical forms in the chain include Old English bedd, Proto-Germanic *gamatô, which anchor the explanation in named linguistic material.