hairline — An extremely thin line or crack; also refers to the edge where hair grows on the head. It describes something so fine it resembles the width of a hair.
Part of speech: NOUN
Definition: An extremely thin line or crack; also refers to the edge where hair grows on the head. It describes something so fine it resembles the width of a hair.
Pronunciation (IPA): /ˈhɛrlaɪn/
Example Sentences
- The detective noticed a hairline scratch on the window that revealed how the burglar entered.
- My dad's hairline is retreating faster than his army days!
- The surgeon made a hairline incision that was barely visible.
hairline
NOUN[/ˈhɛrlaɪn/]
An extremely thin line or crack; also refers to the edge where hair grows on the head. It describes something so fine it resembles the width of a hair.

An extremely thin line or crack; also refers to the edge where hair grows on the head. It describes something so fine it resembles the width of a hair.

A hairline crack reveals the mainline pipeline!
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🎤Pronunciation
🌳Etymology
Origin
From Middle English, combining 'hair' (from Old English hǣr) and 'line' (from Old English līne, ultimately from Latin linea meaning thread or string). Originally referred to the edge where hair grows on the forehead, then extended to mean anything as thin as a hair.
Breakdown
hair (thin strand growing from skin) + line (boundary or thin mark) = hairline (very thin line or the edge where hair meets forehead)
🎵Rhyme
📝Examples
“The detective noticed a hairline scratch on the window that revealed how the burglar entered.”
“My dad's hairline is retreating faster than his army days!”
“The surgeon made a hairline incision that was barely visible.”
“She won the race by a hairline margin - literally by a hair!”
📚Related Words
Synonyms
Antonyms
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