puke
v.v. to vomit or be sick. It is a very informal and slightly gross word for throwing up.
v. to eject the contents of the stomach through the mouth. Often used intransitively, though it can take a direct object; carries a crude or informal tone.
The smell of the old milk made him want to puke.
He spent the entire boat trip leaning over the side because the waves made him puke.
While medical professionals use the term 'emesis', most people in casual settings use 'puke' to describe the physical act of being sick after eating something bad.
Probably imitative; or, alternatively related to Proto-Germanic pukaną (“to spit, puff”), from Proto-Indo-European bew- (“to blow, swell”). If so, then related to German pfauchen, fauchen (“to hiss, spit”), Dutch spugen (“to spit, spit up”), German spucken (“to spit, puke, throw up”), and Old English spīwan (“to vomit, spit”). More at spew. Attested as early as 1581, first mention is the derivative pukishness (“the tendency to be sick frequently”). In 1600, "to spit up, regurgitate", recorded in the Seven Ages of Man speech in Shakespeare's As You Like It.
Often used intransitively, but can be transitive when describing the substance produced.