"man newly married or about to be," Old English brydguma "suitor," from bryd "bride" (see bride) + guma "man," from Proto-Germanic *gumon- (source also of Old Norse gumi, Old High German gomo), literally "earthling, earthly being," as opposed to the gods, from suffixed form of PIE root *dhghem- "earth."
The ending was altered 16c. by folk etymology after groom (n.) "groom, boy, lad" (q.v.). A common Germanic compound (compare Old Saxon brudigumo, Old Norse bruðgumi, Old High German brutigomo, German Bräutigam), except in Gothic, which used bruþsfaþs, literally "bride's lord."
updated on October 23, 2022