Related Clues:

• Buck
• With 15-Across, linguini topping
• Silent one
• Dollar, in slang
• Smacker
• Hardly a blabbermouth
• Symbol of noncommunication
• Shut (up)
• Bisque bit
• Chowder morsel
• Quahog, for one
• One who won't tell
• Symbol of happiness
• "B.C." money
• Steamer, e.g.