Ingrown (adjective)

1. Having grown inwards so as to curve or become embedded in the surrounding tissue.
2. Having become grown in a particular way or place and difficult to remove.

Origin:

Late 17th century (in the sense "grown into the flesh"): from in- "into" + grown.

Examples:

1. She had an ingrown toenail that was causing her a lot of pain.
2. He had a habit of biting his nails, which made them ingrown and difficult to cut.
3. Her hair was so curly and long that it became ingrown and she had to shave it.
4. The tree had ingrown roots that made it impossible to remove from the ground.
5. He had an ingrown personality that made him difficult to get along with.