AGN is a three-letter abbreviation with multiple meanings, as described below:
- Active galactic nucleus
- Acute Glomerulonephritis
- General National Archive (disambiguation)
- Angoon Seaplane Base (IATA: AGN)
- Anderson-Goldstone-Nambu Last names of the people who helped formulate the Higgs mechanism and AGN is short for describing their theory. i.e. AGN boson
- See also
- Egin (disambiguation)