Related Clues:

• Better waterproof
• Performer with a balancing act
• Mark of approval
• Stamped symbol
• Signet
• Shut up tight
• Circus performer, perhaps
• Affix a kiss?
• Waterproof again
• Use again, as a Ziploc
• Organizational symbol, perhaps
• Close hermetically
• Walrus' cousin
• Official emblem
• Use wax on