Definitions of tank:

• noun:   a large (usually metallic) vessel for holding gases or liquids
• noun:   an enclosed armored military vehicle; has a cannon and moves on caterpillar treads
• noun:   as much as a tank will hold
• noun:   a cell for violent prisoners
• noun:   a freight car that transports liquids or gases in bulk
• verb:   store in a tank by causing (something) to flow into it
• verb:   treat in a tank

  Example: "Tank animal refuse"

• name:  A surname (very rare: popularity rank in the U.S.: #19933)