go under

(verb) go under, "The raft sank and its occupants drowned". Synonyms: sink, settle, go down, go under.

(verb) disappear beyond the horizon. Synonyms: set, go down, go under. Example: "The sun sets early these days."

(verb) be called; go by a certain name. Synonyms: go by, go under. Example: "She goes by her maiden name again."