The term 'Kinsey Subject' refers to individuals who participated in the research of Dr. Alfred Kinsey, an American biologist and sexologist. Kinsey conducted a series of studies on human sexual behavior in the 1940s and 1950s, which were later published in two books: Sexual Behavior in the Human Male (1948) and Sexual Behavior in the Human Female (1953). The crossword solution for this term is SEX, which is an appropriate answer given the nature of Kinsey's research.