Clubbing of fingers/toes
/klʌbɪŋ/ /ʌv/
1. [noun] clubbing is changes in the areas under and around the toenails and fingernails that occur with some disorders. The nails also show changes. Common symptoms of clubbing: The nail beds soften. The nails may seem to "float" instead of being firmly attached. The nails form a sharper angle with the cuticle. The last part of the finger may appear large or bulging. It may also be warm and red. The nail curves downward so it looks like the round part of an upside-down spoon. Clubbing can develop quickly, often within weeks. It also can go away quickly when its cause is treated. See: https://www.mountsinai.org/health-library/symptoms/clubbing-of-the-fingers-or-toes ; Accessed May 8 2019
Source: https://www.mountsinai.org/health-library/symptoms/clubbing-of-the-fingers-or-toes

Frequently Asked Questions
How can you relate the appearance of clubbed toenails to everyday objects, like an upside-down spoon?
Clubbing often makes toenails curve downward with a rounded free edge, similar to the bowl of an inverted spoon. This visual cue helps one notice that the nail’s structure is altered, providing a familiar everyday reference for the change in shape.
In what way does the attachment of clubbed toenails differ from normally adhering nails?
Typically, toenails are firmly attached to a solid nail bed. With clubbing, the nail appears to 'float' due to a softening nail bed and a sharper angle at the cuticle, making the normal adhesion less distinct.