IM
- IM – (s) Isle of Man (FIPS 10-4 territory code) – (i) Instant Message (internet speech)
- IMA – (i) Intermediate Maintenance Activity – Institute of Mathematics and Applications
- IMBD – (i) International Migratory Bird Day
- IMDb – Internet Movie Database
- IMF – (i) International Monetary Fund
- IMHO – (i) In My Honest/Humble/Heartfelt Opinion, c.f. IMO.
- IML – (i) International Mister Leather
- IMLAST – (i) International Movement for Leisure Activities in Science and Technology – see MILSET
- IMNM - (i) - Immune-mediated necrotizing myopathy a rare, but serious ADR of statins
- IMNSHO – (i) In My Not So Humble Opinion
- IMO (in my opinion) – (i) In My Opinion, also "imo", c.f., IMHO
- IMPAC – (a) International Merchant Purchase Authorization Card
- IMPACT – (a) International Medical Products Anti-Counterfeiting Taskforce
- IMPATT – (p) IMPact Avalanche Transit Time diode
- IMPT – (i) Institute of Maxillofacial Prosthetists and Technologists
- IMR – (i) Inzhenernaya Mashina Razgrazhdeniya (Russian Инженерные Машины Разграждения, "Engineer Vehicle Obstacle-Clearing") †
- IMRI – (i) Industrial Membrane Research Institute – Information Management Research Institute – Institut pour le management de la recherche et de l'innovation (French, "Institute for the Management of Research and Innovation") – International Market Research Information – Intraoperative Magnetic Resonance Imaging
- IMRO – Internal Macedonian Revolutionary Organization, Irish Music Rights Organisation
- IMRL – (i) Individual Material Readiness List
- IMS – (i) Information Management System – International Meat Secretariat – Ion Mobility Spectrometer
- IMSA – (i) Illinois Mathematics and Science Academy – International Mind Sports Association – International Motor Sports Association
- IMsL – (a) International Ms. Leather
- IMT – (i) Integrated Management Tool
- IMU – (i) International Mathematical Union
Read more about this topic: List Of Acronyms And Initialisms: I