From Longman Dictionary of Contemporary Englishhairlinehair‧line /ˈheəlaɪn $ ˈher-/ noun [countable] 1 DCBthe line around your head, especially at the front, where your hair starts growing He had put on weight, and his hairline was beginning to recede.2 → a hairline crack/fracture
Examples from the Corpus
hairline• I was worried about a hairline fracture, but luckily it was just a bad lump.• A hairline distinction exists between this description of personal experience and the evaluation of a work.• His long bushy eyebrows, mingling with his coarse black hairline, made him appear to have no forehead at all.• Yo mumbles to herself at the windows outlining her hairline with a contemplative index finger.• He still wears a sailor suit, the cowlick at his hairline gives his forelock a life of its own.• My hairline had ascended another inch or so.• By the artistic team at Zoo Ultra short hairline contrasts with thick natural waves.• Apparently, all that yoga stuff doesn't work for the hairline. 