street cred

Zoobiquityを読んでいると、以前（3/23/2011）に調べた記録はありますが、意味を思い出せない表現（"street cred"）が次の様に出てきました。
Self-injury has gained an unintended endorsement by public figures, I, for one, was shocked by Princess Diana's disclosure to the BBC in 1995 that she cut herself with a lemon peeler and a razor blade. ...
Farrell in telling the world about a self-injuring past; their tools included knives, soda can pop-tops, broken glass, cigarettes, lighters, and their own fingers. Cutting's edgy street cred includes feature appearances in angsty teen films like Thirteen and Girl, Interrpted.
私もPrincess Dianaの伝記を読んだ時にダイアナ妃が自傷行為をしていた事を知り驚きました。