Related Clues:

• Worries
• Stews
• Is in a dither
• Broods
• Fingerboard ridges
• Guitar-neck features
• Guitar bars
• Guitar-neck ridges
• Acts the worrywart
• Guitar ridges
• Fingerboard features
• They're found around a neck
• Guitar neck features
• Guides under the strings
• Agonizes (over)