GB uncommon informal noun 1. a highly toxic chemical nerve agent that inhibits the activity of cholinesterase Synonymssarin 2. a unit of magnetomotive force equal to 0.7958 ampere-turns SynonymsgilbertGi 3. a unit of information equal to one billion (1,073,741,824) bytes or 1024 megabytes SynonymsgigabyteG 4. a monarchy in northwestern Europe occupying most of the British Isles; divided into England and Scotland and Wales and Northern Ireland SynonymsUnited KingdomUKGreat BritainBritainUnited Kingdom of Great Britain and Northern Irela Related words Broader terms kingdomcomputer memory unitmagnetomotive force unitorganophosphate nerve agent Parts British IslesEuropean UnionNorth Atlantic Treaty Organizationterabyte Part of EnglandNorthern IrelandScotlandWalesmegabyte WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.