Definition

Noun: A Graafian follicle is a mature, fluid-filled structure in the ovary of a mammal. It contains a developing egg cell (oocyte) and is responsible for its release during ovulation.

Usage

This is a specialized biological and medical term. It is used to describe a specific stage in the reproductive cycle. * The Graafian follicle ruptures to release the egg during ovulation. * Hormonal signals trigger the final maturation of the Graafian follicle. * Ultrasound can be used to monitor the growth of a Graafian follicle.

Advanced Usage

• The term is often used in contrast to earlier stages of follicular development, such as the or .
• It is a key structure in discussions of fertility, reproductive endocrinology, and assisted reproductive technologies (ART).

Variants and Related Words

• Follicle (n): A general term for a small sac or cavity. In biology, it often refers to the ovarian follicle at any stage of development.
• Ovarian follicle (n): The broader category that includes primordial, primary, secondary, and mature (Graafian) follicles.
• Corpus luteum (n): The structure that forms from the remains of the Graafian follicle after ovulation, which secretes progesterone.

Synonyms

• Mature ovarian follicle
• Tertiary follicle (in some classification systems)
• Preovulatory follicle

Notes on Meaning

• The term is eponymous, named after the Dutch physician Reinier de Graaf (1641-1673), who provided an early description of ovarian follicles.
• It specifically denotes the final, pre-ovulatory stage of follicular development, characterized by a large fluid-filled antrum.

Noun

1. a vascular body in a mammalian ovary enclosing a developing egg