Sentence:  [Lisa] Bowleg details how she went about a psychological study of Black lesbian women only to find—in the midst of data collection—that the study had been configured along an additive model of identity that could not account for the <WSD>intersectionality</WSD> of her participants' experiences. 
Meaning of the word marked with <WSD> tags:  The quality or state of being intersectional, that is, of being characterized by intersection ("especially" of multiple forms of discrimination).