AER
- A.E.R. (automobile)
- AER (motorcycles)
- Action For Economic Reforms
- Advanced Engine Research
- Aer (Sendai)
- Aer (album)
- Aer (band)
- Aer Lingus
- Aer language
- AerCap
- Aerides
- Aeronautics at the Summer Olympics
- Agranular endoplasmic reticulum
- Agri-Energy Roundtable
- Air (classical element)
- Alberta Energy Regulator
- Albumin Excretion Rate
- Algoma Eastern Railway
- All England Law Reports
- All-electric range
- American Economic Review
- Annual equivalent rate
- Apical ectodermal ridge
- Army Emergency Relief
- Assembly of European Regions
- Australian Energy Regulator
- Aër
- Eastern Arrernte language
- Sochi International Airport
- Verisk Analytics