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1. a stain, spot, or thickening; in anatomy, an area distinguishable by color or otherwise from its surroundings. Often used alone to refer to the macula retinae.
2. a discolored spot on the skin that is not raised above the surface; called also macule.
3. a corneal scar that can be seen without special optical aids; it presents as a gray spot intermediate between a nebula and a leukoma.
4. macula lutea. adj., adj mac´ular, mac´ulate.
macula atro´phica a white atrophic patch on the skin.
macula ceru´lea a blue patch on the skin seen in pediculosis.
macula cribro´sa a perforated spot or area; one of three perforated areas (inferior, medial, and superior) in the wall of the vestibule of the ear through which branches of the vestibulocochlear nerve pass to the saccule, utricle, and semicircular canals.
macula den´sa a zone of heavily nucleated cells in the distal renal tubule that feed information to the juxtaglomerular cells.
macula fla´va a yellow nodule at one end of a vocal cord.
macula folli´culi follicular stigma.
macula germinati´va germinal area; the part of the ovum where the embryo is formed.
macula lu´tea (macula lu´tea re´tinae) (macula re´tinae) an irregular yellowish depression on the retina, lateral to and slightly below the optic disk; receives and analyzes light only from the center of the visual field.
macula sac´culi a thickening on the wall of the saccule where the epithelium contains hair cells that receive and transmit vestibular impulses.
macula utri´culi a thickening in the wall of the utricle where the epithelium contains hair cells that are stimulated by linear acceleration and deceleration and by gravity.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.
mac·u·la of sac·cule[TA]
the oval neuroepithelial sensory receptor in the anterior wall of the saccule; hair cells of the neuroepithelium support the statoconial membrane and have terminal arborizations of vestibular nerve fibers around their bodies.
Farlex Partner Medical Dictionary © Farlex 2012
The site of the hair cells in the saccule; receptors stimulated by the pull of gravity. These cells generate impulses carried by the vestibular branch of the acoustic nerve.
See also: macula
Medical Dictionary, © 2009 Farlex and Partners