What is "seludong"

Seludong ( Old Malay: Kota Seludong, Jawi script: کوتا سلودوڠ), also known as Maynila, was a major polity located at present-day Manila in the Philippines in the 16th century. A vassal state of the Bruneian Empire, it was one of three major polities that dominated the area around the mouth of the Pasig River before the arrival of the Spanish.