| yellow spot | An oval area of the sensory retina, 3 by 5 mm, temporal to the optic disk corresponding to the posterior pole of the eye; at its centre is the central fovea, which contains only retinal cones. Synonym: area centralis, macula lutea, macular area, punctum luteum, Soemmerring's spot, yellow spot. (05 Mar 2000) |
|---|---|
| kernel spot | <microbiology, plant biology> A fungal disease of pecans that causes irregular brown spots on the nuts, it is caused by Coniothyrum caryogenum. (09 Oct 1997) |
| koplik spot | <dermatology> Small red spots with bluish-white centres on the buccal mucosa (lining of cheek), appearing in the early stages (pre-rash) of measles. (27 Sep 1997) |
| utricular spot | The neuroepithelial sensory receptor in the inferolateral wall of the utricle; hair cells of the neuroepithelium support the statoconial membrane and have terminal arborizations of vestibular nerve fibres around their bodies; sensitive to linear acceleration in the longitudinal axis of the body and to gravitational influences. Synonym: macula utriculi, utricular spot. (05 Mar 2000) |
| flying spot microscope | <instrument> A microscope in which a moving spot of light is imaged in the object plane, the energy transmitted by the specimen being detected with a photoelectric cell; the light source may be a cathode ray tube, a scanning disk or drum, or an oscillating mirror. (05 Mar 2000) |
| focal spot | The site of bombardment by electrons and emission of X-rays from the anode of an X-ray tube. See: focal spot size. (05 Mar 2000) |
| focal spot size | The measured size of a focal spot, a function of its actual size and the angulation of the anode surface. See: focal spot. (05 Mar 2000) |
| forty-spot | <zoology> The Tasmanian forty-spotted diamond bird (Pardalotus quadragintus). Source: Websters Dictionary (01 Mar 1998) |
| Fuchs' black spot | An area of pigment proliferation in the macular region in degenerative myopia. (05 Mar 2000) |
| liver spot | A variably pigmented lentigo occurring on exposed skin of older Caucasians. Synonym: liver spot, solar lentigo. (05 Mar 2000) |