From WordNet (r) 3.0 (2006):
GB
n 1: a highly toxic chemical nerve agent that inhibits the
activity of cholinesterase [syn: sarin, GB]
2: a unit of magnetomotive force equal to 0.7958 ampere-turns
[syn: gilbert, Gb, Gi]
3: a unit of information equal to 1000 megabits or 10^9
(1,000,000,000) bits [syn: gigabit, Gbit, Gb]
4: a unit of information equal to 1000 megabytes or 10^9
(1,000,000,000) bytes [syn: gigabyte, G, GB]
5: a unit of information equal to 1024 mebibytes or 2^30
(1,073,741,824) bytes [syn: gigabyte, gibibyte, G,
GB, GiB]
6: an island comprising England and Scotland and Wales [syn:
Great Britain, GB]