1. a student or trainee who works outside the main institution, especially in a medical or educational setting
Usage: chiefly North American; common in medical and academic contexts

1. relating to or denoting a student or trainee who is based outside the main institution
Usage: less common than the noun form

Examples

• She worked as an extern at the hospital during her third year of medical school.
• The extern program allows students to gain practical experience in real-world settings.
• Many externs go on to secure full-time positions at their placement sites.
• The extern students were supervised by experienced professionals in the field.
• He completed his extern rotation in pediatrics last summer.