Related Clues:

• Large, hard-shelled seed
• Eccentric person
• Hard fruit or informal lunatic
• 'Almond or cashew, say (3)'
• One might be wanting to be one
• Well, it doesn't sound this way
• How one gets noise by the yard from this little bird
• A hard case for 1 down
• The case is hard for one by a washer
• Screwy enough to turn the big vessel over
• Screwy and round the bend
• A hard case in 23 across
• It's hard to be not all there
• The hard one might be a mad man
• You'd be mad to overturn the vessel like this