hairline

== English == === Etymology === From hair +‎ line. === Pronunciation === (US) IPA(key): /ˈhɛɹˌlaɪn/ === Noun === hairline (plural hairlines) The line along one's forehead where hair starts growing. A very thin line in writing, drawing, or typography. A very thin fissure. A fishing line made from hair. ==== Derived terms ==== ==== Translations ==== === Adjective === hairline (figurative) Very thin, as thin as a hair.