"The masculine/feminine binary constitutes not only the exclusive framework in which that specificity can be recognized, but in every other way the "specificity" of the feminine is once again fully decontextualized and separated off analytically and politically from the constitution of class, race, ethnicity, and other axes of power relations that both constitute "identity" and make the singular notion of identity a misnomer" (Bulter 355).
What this sentence is trying to say is that the category of "women" which is defined by the discourses that make up what is "feminine" cannot really be such an all-inclusive category. There are oppressions even within this narrow category because of the power dynamics that have to do with race, class, ethnicity etc. Every woman experiences oppression in a different way because of racial, ethnic, and cultural differences. What Butler means by "specificity" is the notion that there is some sort of characteristic that unites "women" across cultures, yet she argues that this is not so because this definition ignores the social and historical complexities that make up different cultures and peoples. She argues that there is no such "identity" as "woman" that is monolithic and can encompass all every woman; intersectionality is completely overlooked with such a notion.