also bitchen, "good," teen/surfer slang attested from 1950s, apparently from bitch (v.) in some inverted sense. Meaning "complaining" is by 1945, U.S. armed services.
Old English bicce "female dog," probably from Old Norse bikkjuna "female of the dog" (also fox, wolf, and occasionally other beasts), of unknown origin. Grimm derives the Old Norse word from Lapp pittja, but OED notes that "the converse is equally possible." As a term of contempt applied to women, it dates from c.1400; of a man, c.1500, playfully, in the sense of "dog." Used among male homosexuals from 1930s. In modern (1990s, originally black English) slang, its use with reference to a man is sexually contemptuous, from the "woman" insult.
BITCH. A she dog, or doggess; the most offensive appellation that can be given to an English woman, even more provoking than that of whore. ["Dictionary of the Vulgar Tongue," 1811]Bitch goddess coined 1906 by William James; the original one was success.
"to complain," attested at least from 1930, perhaps from the sense in bitchy, perhaps influenced by the verb meaning "to bungle, spoil," which is recorded from 1823. But bitched in this sense seems to echo Middle English bicched "cursed, bad," a general term of opprobrium (e.g. Chaucer's bicched bones "unlucky dice"), which despite the hesitation of OED, seems to be a derivative of bitch (n.).
Good; excellent; superior: A bitchen new single from Southern California has been riding the airwaves to the max this summer/ Because of your bitchin' body, I'm going to put you on hold for a couple of days (1950s+ Teenagers)
Very; extremely: That was a bitching good party