The agency that sets the Internet addressing guidelines influencing how people navigate the Web defeated a proposal Friday to give adult Web sites their own “.xxx” domain.

Many in the adult-entertainment industry and religious groups alike had criticized the plan, which the Canadian government also warned this week could leave the Internet Corporation for Assigned Names and Numbers in the tricky business of content regulation.

The 9-5 decision by ICANN’s board came nearly seven years after the proposal was first floated by ICM Registry LLC. It was the third time ICANN has rejected such a bid. Paul Twomey, ICANN’s chief executive, who had described the proposal this week as “clearly controversial, clearly polarizing” abstained from the vote but did not say why.

“We are extremely disappointed by the board’s action today,” said Stuart Lawley, ICM’s president and chief executive. “It is not supportable for any of the reasons articulated by the board, ignores the rules ICANN itself adopted for the RFP (request for proposal), and makes a mockery of ICANN bylaws’ prohibition of unjustifiable discriminatory treatment.”