What does ALT stand for?

What does ALT mean?

ALT	Anarchists Lunaticts And Terrorists Miscellaneous » Unclassified
ALT	Allegheny Teledyne, Inc. (delisted) Business » NYSE Symbols
ALT	Anti Labour Technican Miscellaneous » Unclassified
ALT	ALTernate key Computing » General
ALT	Abundant Larval Transcript Medical » Laboratory
ALT	Abundant Larval Transcript Medical » Human Genome
ALT	Approach and Landing Test Governmental » NASA
ALT	Altimeter Governmental » NASA
ALT	Acquisition, Logistics, and Technology Governmental » Military
ALT	Analytica Ltd Business » ASX Symbols
ALT	Alanine aminotransferase Medical » Physiology
ALT	Argon laser trabeculoplasty Medical
ALT	Argon laser trabeculoplasty Miscellaneous

elevation, EL, altitude, ALT(noun): angular distance above the horizon (especially of a celestial object)