age
age bracket / age group

blood
blood group

break up
she broke up the class into groups

breakaway
breakaway group

breakout
breakout group

DAG
Domestic Advisory Group

environmental
an environmental group

ethnic
ethnic group

G7
Group of Seven

G8
Group of Eight

ginger
ginger group

group
group booking

high-risk
high-risk group

insurgent
insurgent group

JPEG
Joint Photographic Experts Group

MPEG
Moving Pictures Experts Group

MVEG
Motor Vehicle Emissions Group

pop
pop group

pressure
pressure group

self-help
self-help group

smash up
a group of vandals smashed up two stores

splinter
splinter group

study
study group

support
support group

terror
terror group

therapy
group therapy