Added 9 October 2026 phd noun Categories: LanguageUncommon Words noun ! Definition from WordNet 3.1, Princeton University. More about phd at Wordnik → Where our words come from → A doctorate usually based on at least 3 years graduate study and a dissertation; the highest degree awarded graduate study. Related Words: doctoraldoctoratepostgraduategraduatedegreediplomadissertationcaecommentarythesisthirddiss Back to today's word