Related Clues:

• Essential element of dot-com transactions
• Daily sorting criterion
• '___ your lip!'
• Compress, as a file
• ___ code (number on a letter)
• Mailing code
• 90210, for one
• Letter digits
• 90210, e.g
• City and state follower
• Final part of a US mailing address
• Move with vigor
• Letter number
• Geographic indicator, briefly
• Energy (informal); a US code