| Acronym | Definition |
|---|
| ALT➣Alternative (USENET newsgroup prefix) |
| ALT➣Alternate |
| ALT➣Altitude |
| ALT➣Alto |
| ALT➣Alteration |
| ALT➣Alternating |
| ALT➣Association for Learning Technology |
| ALT➣Alanine Aminotransferase |
| ALT➣Altimeter |
| ALT➣Algorithmic Learning Theory (Conference) |
| ALT➣Radar Altimeter (SEASAT, GEOS-3) |
| ALT➣Adult Learning and Teaching (degree program) |
| ALT➣Assistant Language Teacher |
| ALT➣Argon Laser Trabeculoplasty |
| ALT➣Analogue Loopback Transfer |
| ALT➣Automated Loop Test |
| ALT➣Adaptive Lighting Technology |
| ALT➣Alternative |
| ALT➣Altoona Transportation Center (Amtrak station code; Altoona, PA) |
| ALT➣Alanine Amino Transferase (medical) |
| ALT➣Advanced Learning Technologies |
| ALT➣Acquisition, Logistics, and Technology (US Army) |
| ALT➣Accelerated Life Testing |
| ALT➣Applied Laser Technology (various locations) |
| ALT➣Alternative Lengthening of Telomeres (cells) |
| ALT➣Accelerated Life Test |
| ALT➣Altus AFB (Altus, OK) |
| ALT➣Approach and Landing Test |
| ALT➣Assistant Leader Trainer |
| ALT➣Acquisition Lead Time |
| ALT➣Association for Linguistic Typology |
| ALT➣Allocation Logement Temporaire (French: Temporary Housing Allowance) |
| ALT➣Aboriginal Lands Trust (Department of Indigenous Affairs) |
| ALT➣Alliance for Lobbying Transparency (UK) |
| ALT➣Administrative Lead Time |
| ALT➣Airsoft Lunel Team (French Airsoft group) |
| ALT➣Anarchists, Lunatics and Terrorists (apocryphal origin of newsgroup hierarchy) |
| ALT➣Anti Leech Tracker |
| ALT➣Achievement Level Test |
| ALT➣Approximate Lower Triangular (coding scheme) |
| ALT➣Association for Local Telecommunications |
| ALT➣Army Liaison Team |
| ALT➣Amarillo Little Theatre (Amarillo, TX) |
| ALT➣Associazione per la Lotta Alla Trombosi e Alle Malattie Cardiovascolari (Italian: Association to Combat Thrombosis and Cardiovascular Disease; est. 1986) |
| ALT➣Automatic Link Transfer |
| ALT➣Airborne Laser Tracker |
| ALT➣Advanced Lightning Technology |
| ALT➣Aer Lingus Teoranta |
| ALT➣Automatic Line Testing (Nortel) |
| ALT➣Alanina Amminotrasferasi (Italy) |
| ALT➣Active Leap Technology |
| ALT➣ATM Link Termination |
| ALT➣Associazione Italiana per la Lotta Alla Trombosi |
| ALT➣All Legal Transitions |
| ALT➣Analog Line Termination |
| ALT➣Asynchronous Line Test |
| ALT➣Automatic Line Thresholded |
| ALT➣Alarms and Telemetry (Sprint) |
| ALT➣Aljamiado Learning Technologies (est. 2001) |
ALT - angular distance above the horizon (especially of a celestial object)