A university student, usually already possessing a four year degree, who is working on a master's degree or Ph.D.(noun)
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Use "grad student" in a sentence
"Strier was a grad student in biological anthropology at Harvard, scouting a possible research topic for her doctorate."
"The previous boat disappeared last year in an embarrassing mishap, leaving Ted and a grad student named Ray Radtkey stranded for days on Angel de la Guarda."
"I close my eyes and I am a too-serious, overachieving grad student again."