Related Clues:

• Work one's incisors
• Act like a rat
• Chew, as a beaver
• Sand bits
• Chew on a bone
• Bother (with ''at'')
• Inner fortitude
• ''True ___'' (John Wayne film)
• Chew at
• Exhibit beaver behavior
• Mice and beavers do it
• Cogburn's was ''True''
• Chew on rawhide
• Mimic a mouse
• 'True __'