To feel extreme disgust or revulsion; an idiomatic expression for being nauseated figuratively.
彼のうわさ話を聞いて、反吐が出そうになった。
Hearing his gossip made me feel sick with disgust.
そのやり方には反吐が出るほど腹が立った。
I was so angry at that method that it made me want to vomit (with disgust).
虚偽の答弁を聞いて反吐が出る思いだった。
Hearing the false testimony made me feel revolted.
To vomit; to throw up (used in a literal, physiological sense).
船酔いで朝から何度も反吐が出た。
I threw up several times since morning because of seasickness.
匂いで気分が悪くなり、思わず反吐が出てしまった。
The smell made me sick and I involuntarily vomited.
食べ過ぎて夜中に反吐が出た。
I overate and vomited in the middle of the night.