From Longman Dictionary of Contemporary Englishschoolmateschool‧mate /ˈskuːlmeɪt/ noun [countable] SESsomeone who goes or went to the same school as you
Examples from the Corpus
schoolmate• A new family had to be created, of friends, coworkers and schoolmates.• His sad, excruciatingly well-behaved adolescence is inextricable from the progress of a doomed friendship with an eccentric schoolmate, Smallgods.• It went back to her childhood when she had been teased by her schoolmates about her stammer.• The Phinneys-the parents of his schoolmate Tad-were very sporting about turning their house into an armed camp for the night.• At least for a short time, schoolmates often showed deference to their fallen peers.• Margarett snaps Miss Sheldon, chaperone of the Florentine School, and two schoolmates lounging on deck chairs. 