Page:Adams ex rel. Kasper v. School Board of St. Johns County, Florida (2021).pdf/77

 would lose the protection of the bathroom safe harbor only if the meaning of “sex” unambiguously did not turn on reproductive function.

For its part, the district court ruled that the Board violated Title IX for different but equally flawed reasons. It first ruled that the meaning of “sex” in Title IX was ambiguous because the statute did not define the term and dictionary definitions of “sex” were not “so universally clear” at the time. It then held that our decision in Glenn v. Brumby, 663 F.3d 1312, and the Supreme Court’s decision in Price Waterhouse v. Hopkins, 490 U.S. 228 (1989) (plurality opinion), supported its conclusion that “sex” in Title IX “includes ‘gender identity’ for purposes of its application to transgender students.”

A statutory term is not ambiguous solely because a statute does not define it or because an isolated dictionary suggests a divergent meaning. See Brown v. Gardner, 513 U.S. 115, 118 (1994) (“Ambiguity is a creature not of definitional possibilities but of statutory context … .”). Further, the only purportedly competing definition the district court found—that “sex” means “the character of being either male or female,” Sex, American College Dictionary (1970)—supports a biological meaning of sex. That dictionary defined “female” and “male” in physiological, reproductive terms. See Female, American College Dictionary (1970) (“a human being of the sex which conceives and brings forth young; a woman or girl”); Male, American College Dictionary (1970) (“belonging to the sex