bitch

before 1000; Middle English bicche, Old English bicce; cognate with Old Norse bikkja

How shocked and offended will people be if you use this word? Well, that all depends on how you are using it and what you are referring to. Originally, bitch simply meant a female dog, and it still does. But around the year 1400, it gained currency as a disparaging term for a woman, originally specifically “a lewd or sensual woman,” and then more generally “a malicious or unpleasant woman.” The word is first found used this way in the Chester Plays of the 1400's, which has the line “Who callest thou queine, skabde bitch?,” translated by one writer into modern English as “Who are you calling a whore, you miserable bitch?” By the 1800's, bitch was considered “the most offensive appellation that can be given to an English woman,” to the point where people started using euphemisms for the literal sense, such as lady dog and she dog.
But language keeps evolving, and bitch can now also be applied to a man, to a complaint, and to any difficult or unpleasant thing or situation. Used as a verb, we can talk about complaining (“bitching and moaning”), or bungling things (“bitching something up”), or riding in an uncomfortable position in a car (“sitting bitch”). When used in any of these ways, it's more slang than vulgarity, more colorful interjection than cause for offense. In fact, bitch has been reclaimed by some women as a self-referential term of empowerment. Nevertheless, care must be taken—there is a big difference between bitching about a woman and calling her a bitch! (Though it's O.K. to call her female dog that.)

— The BITCH Manifesto: Classic feminist article (1970) written by Jo Freeman under the pen name Joreen. It reclaimed the word “bitch” as a term of empowerment rather than one of abuse.
— Bitch: A feminist magazine commenting on popular culture and media, founded in 1996.
—Bitch: The stage name of a politically outspoken female rock vocalist/violinist and actress.
— Skinny Bitch: A diet book (2005) written by Rory Freedman and Kim Barnouin.
— No One's the Bitch: A book (2009), website, and forum that supports mother and stepmother relationships. Started by Jennifer Newcomb Marine and Carol Marine.
—Stitch 'n Bitch: A network of groups of people who knit and crochet.

bitch + -in’, -en  informal or dialectal variant of -ing² (here forming nonparticipial adj.)