Senses
阿哥 elder brother
(familiar) elder brother; used as a term of address in certain dialects
阿哥 prince
(historical) term for a son of an emperor during the Qing dynasty who had not yet reached adulthood or received a title
阿哥 brother
(literary) used as a respectful or common form of address for a male contemporary, often seen in early vernacular literature like 水浒传