Hairpin (noun)

1. A pin that is used to fasten the hair in a specific style.
2. A hair accessory that has a U-shaped end that is used to secure a bun or other hairstyle.

Origin:

From old english hær ("hair") + pin ("pi.n")

Examples:

1. She used a hairpin to keep her hair in place.
2. He gave her a hairpin so she could fix her hair.
3. The hairpin was decorated with small flowers.
4. She had a collection of hairpins in different colors and shapes.
5. The hairpin was made of metal and had a curved shape to hold the hair securely.