Hangnail is a piece of torn skin at the root of a fingernail
If you are a nail biter, it's likely that you develop more hangnails than your friends. Biting your nails can damage your nail bed, which is the skin underneath the actual fingernail.
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Another cause of hangnails is a manicure gone awry -- an inept hand with the nail clippers or frequent cutting of the cuticles can cause hangnails.