1. (cosmology) one billion (10^9) years
   "the universe is approximately 14 gigayears old"

Encyclopedia: Gigayear

• dark-spotted
• darken
• darkened
• darkener
• darkening
• darkey
• darkie
• darkish
• darkle
• darkling
• darkling beetle
• darkling groung beetle
• darkly
• darkness
• darkroom
• darksome
• darky
• darling
• darling pea
• Darling River
• Darlingtonia
• Darlingtonia californica
• Darmera
• Darmera peltata
• darmstadtium