A person taking part in practical work experience at a company or organization (an intern), or the internship arrangement itself.
夏休みにIT企業でインターンをした。
I did an internship at an IT company during summer vacation.
その大学生はインターンを経て正社員になった。
That university student became a full-time employee after doing an internship.
インターン期間は通常二週間から三か月だ。
The internship period is usually from two weeks to three months.
インターンに応募するには履歴書が必要だ。
You need a CV to apply for an internship.