1. (astronomy) a collection of star systems; any of the billions of systems each having many stars and nebulae and dust
   "'extragalactic nebula' is a former name for 'galaxy'"
   - galaxy

Derived forms: extragalactic nebulae

Type of: accumulation, aggregation, assemblage, collection

Part of: cosmos, creation, existence, macrocosm, universe, world

• Theridiidae
• therm
• thermal
• thermal barrier
• thermal emission
• thermal equilibrium
• thermal pollution
• thermal printer
• thermal reactor
• thermal resistor
• thermal spring
• thermalgesia
• thermalise
• thermalize
• thermally
• thermel
• thermic
• thermic fever
• Thermidor
• thermion
• thermionic
• thermionic current
• thermionic emission
• thermionic tube
• thermionic vacuum tube