hair follicle

noun

: the tubular epithelial sheath that surrounds the lower part of the hair shaft and encloses at the bottom a vascular papilla supplying the growing basal part of the hair with nourishment see hair illustration

Examples of hair follicle in a Sentence

Recent Examples on the Web

Sold under the brand names Proscar and Propecia among others, finasteride works by blocking the enzyme 5α-reductase, which changes testosterone into dihydrotestosterone (DHT), the hormone that causes AGA hair follicles to shrink. —Pranjal Malewar, New Atlas, 18 Oct. 2025

The team is also investigating whether cysteine could stimulate hair follicle regeneration, with plans to further explore other amino acids that appear to influence stem cell regeneration. —Deirdre Bardolf, FOXNews.com, 16 Oct. 2025

Cold capping works by lowering the temperature of the scalp before and during chemotherapy to restrict blood flow to hair follicles and reduce the amount of chemo that reaches them. —Liz Neporent, ABC News, 6 Oct. 2025

Some studies suggest that onion juice can improve circulation to the hair follicles—Yates recommends pairing with a scalp massage—which may encourage hair regrowth for some people. —Grace McCarty, Glamour, 2 Oct. 2025

Word History

First Known Use

1838, in the meaning defined above

Rhymes for hair follicle

• diabolical
• symbolical

Kids Definition

hair follicle

noun

: the tube-shaped sheath surrounding the lower part of a hair shaft

Medical Definition

hair follicle

noun

: the tubular epithelial sheath that surrounds the lower part of the hair shaft and encloses at the bottom a vascular papilla supplying the growing basal part of the hair with nourishment