That thats; unstressed thuhts ; bush boosh means "That is bull $hit." The "bu" is the first two letters from the word "bull" and the "sh" is the first two letters from the word "$hit" Creating the term, "That's bush." Another way of saying "that's b.s."
"He got an "A" even though he cheatedon the test. That's bush."
"That's bush, you didn't even know her."
Guy 1: So I finally got to see Sarah naked last night.
Guy 2: Nice! How kept are the greens?
Guy 1: Not kept at all, she had That 70's Bush.
Guy 2: Damn...