Sihing or Shixiong means senior fellow students in a Chinese martial art school. Si means teacher. Hing means elder brother. The seniority is not based on the student's age or level of skill, but on the chronological order of following a particular sifu. The master's first student is always the most senior shihing . The less senior students are called sidai among their peers.
Today, at least in Hong Kong, students from the same school will informally refer to their peers in the years above them as sihing or sizhe , and peers in the lower years to their own as sidai or simui . This practise also extends to the Hong Kong Police and other certain uniformed groups.