Defining Male and Female Act of 2025

This bill would set one national, biological definition for words like male, female, man, woman, boy, girl, father, mother, and sex for all federal laws and rules. It says sex is an unchanging biological status set at conception. Female is defined by the body’s ability to produce eggs, and male by the body’s ability to produce sperm. It also says “gender identity” is an internal feeling that is separate from biology and will not be used by the federal government in place of sex for legal purposes.

Key points

• What changes: Creates uniform definitions of sex-based terms across all federal laws and agency rules; does not accept gender identity as a substitute for sex in federal law.
• Who is affected: Federal agencies and anyone covered by federal laws and regulations that use these terms.
• How terms are defined: Male/female are based on reproductive biology; man/woman and boy/girl are adult/minor versions; father/mother are male/female parents; sex is an immutable biological classification.