Definition

1. Noun:
   • A small, U-shaped pin used to secure hair in place: A hairpin is a simple, typically metal, fastener formed into a tight U-shape, designed to hold sections of hair securely against the head. It is a classic tool for hairstyling.
   • A sharp bend in a road: In road and track terminology, a hairpin is a very tight, often 180-degree, turn that resembles the shape of a hairpin. This usage is almost exclusively seen in the compound term "hairpin bend" or "hairpin turn."

Examples of Usage

• Noun (Hair fastener):
  • She used a simple hairpin to keep the stray strands away from her face.
  • The antique box was filled with pearl-tipped hairpins.
• Noun (Road feature):
  • The mountain road is famous for its dangerous hairpins.
  • Drivers must slow down significantly for the upcoming hairpin bend.

Advanced Usage

• "Hairpin trigger": This is a metaphorical or technical term describing an extremely sensitive trigger mechanism, one that requires very little pressure to activate, akin to the slight pressure needed to open a hairpin.
  • The political situation had a hairpin trigger, with tensions ready to explode at any moment.
• "Hairpin ligation": A specialized term in molecular biology referring to a technique where a DNA or RNA strand forms a loop (like a hairpin) and is then joined.
  • Hairpin ligation is a key step in the formation of certain RNA structures.

Variants and Related Words

• Hairpin bend/turn (n.): The full compound term for a very sharp bend in a road or path.
  • The cyclists struggled with the steep climb and the series of hairpin turns.
• Hairgrip (n., chiefly British): A synonym for a hairpin, especially a flat, often wavy, type.
• Bobby pin (n., chiefly North American): A type of flat hairpin with closed, pronged tips.

Synonyms

• Hair fastener: A general term for any device used to hold hair.
• Grip: A short term for hairgrip.
• Switchback: A synonym for a hairpin bend, especially on a trail or road.

Related Phrases

• To secure with a hairpin: The typical verb phrase describing the action.
  • She secured her bun with several hairpins.
• To navigate a hairpin: A phrase used in driving or cycling contexts.
  • He skillfully navigated the hairpin without losing speed.

Related Idioms

• "Tighter than a hairpin turn": An idiom used to describe something extremely constricted, narrow, or difficult to maneuver through.
  • The alleyway was tighter than a hairpin turn.
• "Not a hairpin to her name": A hyperbolic idiom suggesting someone is very poor or has very few possessions.
  • When she arrived in the city, she didn't have a hairpin to her name.

Noun

1. a double pronged pin used to hold women's hair in place