Senators struck down the Human Rights Amendment Act by a 5-6 vote margin after a seven-hour debate.
“Man, woman and child is of the highest order,” said Sen. Marc Daniels of the Progressive Labor Party, according to the Royal Gazette newspaper. “That union cannot be mimicked by any other combination.”
The bill — known as the Human Rights Amendment Act — passed last Friday in the Bermuda House of Assembly, which is the lower house of the territory’s Parliament.
Voters in the British territory last month overwhelmingly rejected marriage and civil unions for same-sex couples in a non-binding referendum.
Bermudian lawmakers in 2013 approved a bill that bans discrimination based on sexual orientation.