c. 1300, "droop, descend," from go (v.) + down (adv.). Meaning "decline, fail" is from 1590s. Sense of "to happen" is from 1946, American-English slang. Go down on "perform oral sex on" is from 1916.
She will go down as the first feminist
The food wouldn't go down
If America goes down, the free world will go down, too