Origin: Latin suffix -ate
Postgraduate has 4 different meanings across 2 categories:
a student who continues studies after graduation
"After earning her bachelor's degree, she enrolled in postgraduate courses to specialize in advanced research methods."
A person continuing to study in a field after having successfully completed a degree course.
"After graduating from university, she became a postgraduate student focusing on advanced research in molecular biology."
In plain English: A postgraduate is someone who has already finished their first university degree and is now studying for an advanced qualification at college or university.
"He decided to become a postgraduate after finishing his bachelor's degree."
Usage: Use this noun specifically for an individual who has already earned their first university degree and is now pursuing further advanced training, such as a master's or doctorate. Do not use it to describe the courses themselves; instead, refer to those programs simply as postgraduate studies.
Of studies which take place after having successfully completed a degree course.
"She decided to pursue postgraduate research at Oxford University immediately after graduating with her bachelor's degree in history."
In plain English: Postgraduate describes something related to studies you do after finishing your regular high school degree program.
"The postgraduate program at that university is very competitive."
The word combines the prefix post- with graduate to mean someone who has completed a degree and is continuing their studies at a higher level. It entered English as a straightforward description of advanced academic work following an initial graduation.