ingrown

Concise Oxford English Dictionary © 2008 Oxford University Press:
ingrown/ˈɪnɡrəʊn/

▶adjective

• 1 growing or having grown within; innate: ingrown habit.

• 2 inward-looking.

• 3 (of a toenail) having grown into the flesh.

– derivatives
ingrowing adjective,
ingrowth noun.