Sentence:  Another study by Donnelly of seventy-seven <WSD>incels</WSD> in marriages or long-term relationships in the "Journal of Marriage and Family" used a web-based questionnaire to ask people why they stayed in their sexless relationships (defined in this case as no sex for six months). 
Meaning of the word marked with <WSD> tags:  Anyone who is not sexually active despite desiring to be.