Related Clues:

• Run a tight ___
• Seafarer's vessel
• Pirate's vessel
• Cruise liner or yacht
• Root for as a couple
• Dispatch a tiny drink astride horse
• Mail in a box?
• Send head of security in
• Send (off)
• Use 55-Down, say
• Send via UPS or USPS
• Endorse as a couple, in slang
• Craft in a fleet
• Pequod, for Captain Ahab
• Right boards used to be swinging in frigate, say