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

Encyclopedia: Gigayear

• snuggling
• snugly
• snugness
• so
• so far
• so long
• so much
• so that
• so there
• so to speak
• so what
• so-and-so
• so-called
• so-so
• soak
• soak through
• soak up
• soakage
• soakaway
• soaked
• soaker
• soaking
• soaking up
• soap
• soap bubble