1 definition by Keswick from the UG Forum mma.tv

"Built Like A Fighter"

Used in mma circles, especially the UnderGround Forum at mma.tv, to describe someone who is not actually an mma fighter, but is built like one. Reputed origin is an article describing Dana White, President of the UFC, as "built like a fighter"; hence, to date, blaf has most often been used in reference to Dana White.
Dana White, the bald-headed, f-bomb dropping, egomaniac, delusional, petty President of the UFC, may not technically be an mma fighter himself, but he is most definitely BLAF!
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