- A tiny ball-shaped structure in the kidney composed of capillary blood vessels actively involved in the filtration of the blood to form urine. The glomerulus is one of the key structures that make up the nephron, the functional unit of the kidney. The glomerulus was so named by the Italian anatomist Marcello Malpighi (1628-1694). The structure was once called a malphigian corpuscle. "Glomerulus" is the diminutive of the Latin "glomus" meaning "ball of yarn." It is literally a "little ball of yarn." Plural: glomeruli.
* * *1. A plexus of capillaries. 2. A tuft formed of capillary loops at the beginning of each nephric tubule in the kidney; this tuft with its capsule (Bowman capsule) constitutes the corpusculum renis (malpighian body). SYN: malpighian g., malpighian tuft. 3. The twisted secretory portion of a sweat gland. 4. A cluster of dendritic ramifications and axon terminals forming a complex synaptic relationship and surrounded by a glial sheath. SYN: glomerule. [Mod. L. dim. of L. glomus, a ball of yarn]- juxtamedullary g. a g. close to the medullary border.- malpighian g. SYN: g. (2).- g. of mesonephros one of the tufts of capillary vessels within the mesonephros derived from a lateral branch of the primary aorta; each g. is connected to a tubule.- olfactory g. one of the small spherical territories in the olfactory bulb in which dendrites of mitral and tufted cells synapse with axons of olfactory receptor cells.- g. of pronephros one of the tufts of capillary vessels in the pronephros derived from a lateral branch of the aorta.
* * *glo·mer·u·lus glə-'mer-(y)ə-ləs, glō- n, pl -li -.lī, -.lē a small convoluted or intertwined mass (as of organisms, nerve fibers, or capillaries): asa) a tuft of capillaries that is covered by epithelium, is situated at the point of origin of each vertebrate nephron, and normally passes a protein-free filtrate from the blood to the surrounding Bowman's capsule see RENAL CORPUSCLEb) the convoluted secretory part of a sweat glandc) a dense entanglement of nerve fibers situated in the olfactory bulb and containing the primary synapses of the olfactory pathway
* * *n. (pl. glomeruli)1. the network of blood capillaries contained within the cuplike end (Bowman's capsule) of a nephron. It is the site of primary filtration of waste products from the blood into the kidney tubule.2. any other small rounded mass.
* * *glo·mer·u·lus (glo-merґu-ləs) pl. glomerґuli [L., dim. of glomus ball] 1. a tuft or cluster; used in anatomic nomenclature as a general term to designate such a structure, as one composed of blood vessels or nerve fibers. 2. g. renis.
Medical dictionary. 2011.