Definition: to become unconscious.
(This phrasal verb has more than one meaning)
E.g.1: She felt dizzy and then passed out but luckily someone caught her before she hit the ground.
E.g.2: I remember climbing the ladder, but I can’t remember the accident. I guess I must have passed out, because the next thing I remember was the paramedic looking down at me.
This phrasal verb cannot be separated by a pronoun.