HJ

Look up hj in Wiktionary, the free dictionary.

HJ may refer to:

Science, technology, and mathematics:

• Hall–Janko group, a mathematical group
• Heterojunction, the interface between two layers of dissimilar crystalline semiconductors
• U.S. code for a cryptographic key change; see cryptoperiod

Other uses:

• ⟨hj⟩, a two-letter combination used in some languages
  • hj-reduction, a process affecting the pronunciation of English words like human in some dialects
• Holden HJ, An Australian full sized car produced between 1974 & 1976
• Hajji (Hj.), an Islamic honorific
• Halliwell Jones Stadium, a stadium in Warrington, England, know as 'The HJ'
• Handjob, in sexual slang
• hic jacet ('here lies'), commonly used on gravestones; see List of Latin phrases (H)
• Hilal-i-Jurat, the second highest military award of Pakistan
• Hitler-Jugend, the German name for the Hitler Youth
• Tasman Cargo Airlines (IATA airline designator HJ)