hairline

髮際線、髮線

He noticed his hairline had started to recede in his thirties.

他發現自己三十幾歲時髮際線就開始後退了。

細縫、細紋、細線

There was a hairline in the glaze of the old teapot.

那只舊茶壺的釉面上有一道細縫。

極細的、細微的

The X-ray showed a hairline fracture in her wrist.

X光顯示她的手腕有一道細微的骨裂。