221 (disambiguation)

221 may refer to:

In time:

• The year:
  • 221 AD
  • 221 BC

In mathematics:

• 221 (number)

In geography:

• Roads:
  • U.S. Route 221 in Virginia

In astronomy:

• 221 Eos, a main-belt asteroid

In transportation:

• Aircraft:
  • The Boeing 221 mail plane
• Rail:
  • 221 series, a type of train in Japan

In weapons:

• Firearms:
  • The .221 Remington Fireball pistol cartridge

In fiction:

• 221B Baker Street, the address of Sherlock Holmes
• Experiment 221, the codename for Sparky, a fictional alien character in the Lilo & Stitch franchise