SIJ
SIJ stands for:
- Siglufjörður (IATA code), Fjallabyggð municipality in the Norðurland eystra region, Iceland
- Seco International (ICAO code), Japanese airline
sij stands for:
- Numbami (also: Siboma or Sipoma; ISO-639-3 code), one of the Oceanic languages
- Si (civil servant)
