海口 Traditional form: 海口 Pinyin (reading): Hǎikǒu Definitions: Haikou prefecture-level city and capital of Hainan Province 海南省 ( Hǎinán Shěng) Characters: 海 - sea, ocean; maritime 口 - mouth; entrance, gate, opening Traditional characters: 海 - sea, ocean; maritime 口 - mouth; entrance, gate, opening