| A/N | Above Named 
| Others |
| A/N | AlphaNumeric
| Others |
| A/N | Anti Natal
| Others |
| A/N | Author's Note
| Others |
| AN | Absolutely Nowwhere
| Others |
| AN | Access Node
| Others |
| AN | Accessory Number
| Others |
| AN | Account Number
| Others |
| AN | Acid Number
| Others |
| AN | Acoustic Neuroma
| Others |
| AN | Acquired Nystagmus
| Others |
| AN | Acrylonitrile AN
| Others |
| AN | ada AN
| Others |
| AN | Ada National
| Others |
| AN | Added Neutrons
| Others |
| AN | Adequate Nutrition
| Others |
| AN | Adult Nationals
| Others |
| AN | Advanced Negative
| Others |
| AN | Agricultural Nutrient
| Others |
| AN | Ai An
| Others |
| AN | Aircraft National
| Others |
| AN | Airman
| Others |
| AN | Airworthiness Notice
| Others |
| AN | Akademija Nauk
| Others |
| AN | Alaska Native
| Others |
| AN | Alianza Nacional
| Others |
| AN | All Natural
| Others |
| AN | Almost Nil
| Others |
| AN | Alpha-Numeric
| Others |
| AN | Alternative National
| Others |
| AN | American Names
| Others |
| AN | American Native
| Others |
| AN | Ammonium Nitrate
| Others |
| AN | Analog Nonsecure
| Others |
| AN | Anchorage Field Office
| Others |
| AN | Ancona (Provence)
| Others |
| AN | Andaman and Nicobar Islands
| Union Territory |
| AN | Anime Nation
| Others |
| AN | Anime North
| Others |
| AN | Anna Nezabava
| Others |
| AN | Annon And No
| Others |
| AN | Anorexia Nervosa
| Others |
| AN | anotherReallyLongName an
| Others |
| AN | Anti Nig
| Others |
| AN | Any Nucleotide
| Others |
| AN | Any Number
| Others |
| AN | Apalachicola Northern Railroad
| Others |
| AN | Apalachicola Northern Railroad (AN Railway)
| Others |
| AN | Applications Note
| Others |
| AN | Architecture Neutral
| Others |
| AN | Archive Note
| Others |
| AN | Archives Nationales
| Others |
| AN | Army Navy
| Others |
| AN | Army Nurse
| Others |
| AN | Army/Navy
| Others |
| AN | Aron Nichols
| Others |
| AN | As Needed
| Others |
| AN | Assignee Name
| Others |
| AN | Associate of Nursing
| Others |
| AN | Asymptotically Normal
| Others |
| AN | Atharv Naik
| Others |
| AN | Athletic Nerds
| Others |
| AN | Attribute Name
| Others |
| AN | Attribute Noise
| Others |
| AN | Author's Notes
| Others |
| AN | Authors Note
| Others |
| AN | Authors Notes
| Others |
| AN | Autonetics
| Others |
| AN | Auxiliary Network
| Others |
| AN | Nauru
| Others |
| AN | Netlayer (Auxiliary, Netlayer)
| Others |
| an. | altnordisch
| Others |