www.alphadictionary.com

From online Etymology:
bask
1393, basken "to wallow (in blood)," from O.N. baðask reflex. of baða "bathe" (see bathe). Modern meaning "soak up a flood of warmth" is apparently due to Shakespeare's use of the word in reference to sunshine in "As You Like It" (1600).

I think it's interesting how this word's meaning changed from one that gave the feeling of distress to that of content.

I left him basked between the dead.

I've been wondering why bask is to wallow in blood. It took me a while, but I think I've figured it out.

Our usual use of bask is for enjoying the warmth of the sun's rays, or the warm feeling of being "tight" with a lord and master type. Well, blood is rather warm when it first comes out, so there you go.

For wallow, see this post.