A way of saying "Good for you!" or "Kudos." Also see bully.

It wasn't always used in a sarcastic tone, but considering how it's changed over time, people do use it in that way.

"In older times, the word 'bully' also had a couple of positive meanings, the only trace of which is left in the expression 'bully for you,' which is still occasionally used in British English - I can't comment on US English. I've mostly heard it used in a derisive or sarcastic way, along the lines of 'Well then, aren't *YOU* the clever one?'"
-Ask.com topic

Referring to women who are sexually or romantically attracted to other women. Applies to both lesbians and bisexual women, as it is only the same-sex attraction that matters, not any other attractions the women may have.

Originates from the Greek poet Sappho, a bisexual woman from the Isle of Lesbos, from which we get the term lesbian.

"bully for you" meaning "good for you". The meaning of bully has changed over time, so no one uses it as much