Verb

(obsolete) To go or move under or beneath.

To experience; to pass through a phase.

* {{quote-magazine, date=2013-01-01

, author=Paul Bartel, Ashli Moore , title=Avian Migration: The Ultimate Red-Eye Flight , volume=101, issue=1, page=47–48 , magazine= citation , passage=Many of these classic methods are still used, with some modern improvements. For example, with the aid of special microphones and automated sound detection software, ornithologists recently reported […] that pine siskins (Spinus pinus ) undergo an irregular, nomadic type of nocturnal migration.}}

The project is undergoing great changes.

To suffer or endure; bear with.

The victim underwent great trauma.

She had to undergo surgery because of her broken leg.