A combination of being a bitch, a pussy, and a tool. Usually brought about in situations where one points out that said person is being a pussy, thus they start acting like a bitch and/or tool as a result of this observation.
Bro, Jon and I were gonna go chill, then he went all bitchsalad and hung out with his girlfriend.
When you're headed out the door to go get lunch and your boss asks you to swing by McDonald's on the way back and pick him up a South West Chicken Salad.
Boss to Employee: "Hey can you grab me a salad from McDonald's on your way back?"
Employee to Boss: "Uhm, we're not going to McDonald's for lunch tho."
Boss to Employee: "On your way back.."
Me to Employee: "Wow, he really made you his bitch right there. he was all like 'Bitch get me some Salad'..
Employee to me: "yep.. it's a BITCH SALAD!"