A person who refrains from being sexually active is celibate. "They dated for three years in high school but committed to staying celibate until marriage — something they were grateful for after breaking up and marrying others when they got older.
While celibate comes from a 17th-century Latin term for "unmarried," today it's used for all people who don't engage in sexual activity. Priests and nuns vow to remain celibate as part of their religious commitments, and many youth groups and religious organizations promote staying celibate until marriage. As a noun, a celibate refers to one who practices celibacy — like the priests and nuns we mentioned.