g=g (grips equal and good)

G6-PD (glucose 6 phosphate dehydrogenase)

G6P (glucose 6 phosphate)

G6PD (glucose-6-phosphate dehydrogenase)

Ga (gallium [element])

GA (granuloma annulare)

GA (gestational age)

GA (general anesthesia)

GABA (gamma-aminobutyric acid)

GABAB (gamma-aminobutyric acid type b)