1. One quintillion (10^18)

Encyclopedia: Exa-

• western wood pewee
• western yellow pine
• western yew
• westerner
• Westernisation
• westernise
• Westernization
• westernize
• westernmost
• westing
• Westinghouse
• westland pine
• Westminster
• Westminster Abbey
• westmost
• Weston
• Weston cell
• Weston-super-Mare
• westside
• westward
• westwards
• wet
• wet bar
• wet behind the ears
• wet blanket