anisotropic

irregular cluster

barred spiral galaxy

irregular galaxy

clusters (of galaxies)

isotropic

dark-matter problem

lenticular galaxy

distance ladder

Local Group

dwarf elliptical galaxy

maser

elliptical galaxy

poor cluster

exotic dark matter

redshift

fundamental plane

regular cluster

galactic cannibalism

rich cluster

giant elliptical galaxy

spiral galaxy

gravitational lens

standard candle

groups (of galaxies)

starburst galaxy

Hubble classification

supercluster

Hubble constant

Tully-Fisher relation

Hubble flow

tuning fork diagram

Hubble law

void

intracluster gas