go under

English

go under (third-person singular simple present goes under, present participle going under, simple past went under, past participle gone under)

To descend into a body of water; to founder.
the boat was too heavy and went under.
(idiomatic) To collapse or fail, e.g. by going bankrupt.
In the crisis, the company was forced to reduce its costs in order to avoid going under.
(idiomatic) To be named; to call oneself.
He goes under the name of Mr X to remain anonymous.
To enter a state of hypnosis.

to descend into a body of water

to fail by going bankrupt — see go bankrupt

to be call oneself

to enter a state of hypnosis