群

rivalry of local warlords; a number of powerful (talented, influential) persons standing by themselves in a given field

to swarm; to crowd; to flock together

Medicine

burnout syndrome

to crowd together

mass psychology; mob psychology; crowd psychology

herd mentality; group mind

Medicine

savant syndrome

Psychology

Stockholm syndrome

to gather in large groups

Perseids

youthful crowd; crowd of young people coming into their own

Medicine

economy class syndrome (occurrence of deep vein thrombosis in air travelers)

Work of art, literature, music, etc. name

Gunsho Ruiju (collection of Japanese classics sorted by type; orig. ed. 1819; comp. ed. 1911)

Military

carrier strike group; CSG

Computing

data aggregate; data constellation

to be crowded with people

fishfinder

to stand all around (e.g. bamboo, pines, pampas grass)

Medicine

sick building syndrome; SBS

Leonids

Medicine

Down's syndrome

Medicine

respiratory distress syndrome

Medicine

Asperger syndrome; Asperger's syndrome; Asperger's

Medicine

sleep apnea syndrome; SAS

Medicine

Munchausen's syndrome