Definition of follicle in US English:



  • 1Anatomy
    A small secretory cavity, sac, or gland.

    • ‘Associated with the follicle are sebaceous glands and the arrector pili smooth muscle fiber bundle.’
    • ‘These drugs penetrate the follicle and sebaceous gland well and decrease colonization by P. acnes.’
    • ‘Inside the gland, multiple follicle pouches join to form excretory ducts, which empty into the urethra.’
    • ‘Retention of the sebaceous secretions, and dilation of the follicle, may lead to cyst formation.’
    • ‘Then, a fluidfilled space develops, to form the antrum of a tertiary follicle.’
    bag, pouch, bladder, blister
    View synonyms
    1. 1.1 The sheath of cells and connective tissue which surrounds the root of a hair.
      • ‘This ingredient exfoliates the surface of the skin and reduces inflammation in the hair follicle, helping the hair to break through.’
      • ‘Further, research also shows that Benzoyl Peroxide will get rid of the hair follicle of dead cells to prevent further plugging of pores.’
      • ‘An expensive and often painful procedure, it involves inserting a needle directly into the hair follicle to electrocute the root.’
      • ‘Genetic profiling revealed 97 genes that were ‘switched on’ in the hair follicle stem cells.’
      • ‘The oily sebum rises up through the hair follicle, providing lubrication for your skin and hair.’
      • ‘They result when oil, dead skin cells and bacteria trapped in the hair follicle cause it to swell and eventually burst.’
      • ‘When DHT is produced locally within the hair follicle, it causes regular hairs to turn into miniature hairs, eventually killing the hair follicle.’
      • ‘Folliculitis presents with a subcorneal pustule in the opening of a hair follicle, with surrounding neutrophilic infiltrate.’
      • ‘But with first-time waxers, the hair follicle is often surrounded by something similar to a whitehead, so when you rip it out it can cause a bit of bleeding.’
      • ‘Electrolysis involves inserting a needle under your skin in order to zap an electric current through your hair follicle and damage it.’
      • ‘Eventually the hair follicle dies and the hair is permanently lost.’
      • ‘The cells that supply the hair follicle remain active, so the potential for re-growth is always there.’
      • ‘No one had been able to isolate stem cells from the hair follicle in this way before.’
      • ‘Acne is a disorder of the pilosebaceous unit, which is made up of a hair follicle, sebaceous gland and a hair.’
      • ‘The hair follicle is located under the skin, houses the hair bulb and root, and is responsible for the hair's growth.’
      • ‘Pro-vitamin B5 and zinc serve as backup, latching on to the binding sites in the hair follicle where DHT would do its damage.’
      • ‘Laser systems emit a beam of light that passes through the skin to the hair follicle.’
      • ‘Tiny needles are inserted into the hair follicle followed by an electrical charge that damages it, causing it to stop producing hair.’
      • ‘The usual remedies for unwanted hair include plucking, shaving, waxing or chemical depilatories, but all of them are temporary, as none damage the hair follicle.’
      • ‘In hair follicle cells, for example, the wingless gene changes stem cells to skin cells.’
    2. 1.2
      • ‘And your brain is putting out follicle stimulating hormone, trying to get the ovary to respond.’
      • ‘De Graaf, working without the aid of a microscope, made the error of thinking that the fluid-filled follicles were the ova themselves.’
      • ‘In most normal human menstrual cycles only one follicle reaches full maturity, to be released at ovulation, on about day 14.’
      • ‘The ovary consists of a cortical zone composed of a specialized stroma, which contains follicles with ova.’
      • ‘A value of less than 10 antral follicles suggests reduced ovarian reserve.’
  • 2Botany
    A dry fruit that is derived from a single carpel and opens on one side only to release its seeds.

    • ‘To sow the seed, allow the pods, or follicles, to ripen on the tree.’
    • ‘The three fruits that were formed by flowers in the emasculation treatment were single follicles.’
    • ‘If you wish to sow, allow plumeria seed pods, or follicles, to ripen on the tree.’
    • ‘The fruits produced by these partially emasculated flowers were single follicles and contained relatively few seeds.’
    • ‘A fruit may consist of a single follicle or two joined follicles.’


Late Middle English: from Latin folliculus ‘little bag’, diminutive of follis ‘bellows’.