any of four tracts of descending motor fibers that extend in pairs down each side of the spinal column and function in voluntary movement.
pyramidal tract n.
A massive bundle of fibers that originates from the motor cortex and the postcentral gyrus and emerges on the ventral surface of the medulla oblongata. Most of the fibers cross to the opposite side in the pyramidal decussation and descend the length of the spinal cord to innervate muscles of the extremities.
[pahy-ruh-man-see] /ˈpaɪ rəˌmæn si/ noun 1. divination by fire, or by forms appearing in fire. /ˈpaɪrəʊˌmænsɪ/ noun 1. divination by fire or flames
[pahy-rom-i-ter] /paɪˈrɒm ɪ tər/ noun 1. an apparatus for measuring high temperatures that uses the radiation emitted by a hot body as a basis for measurement. /paɪˈrɒmɪtə/ noun 1. an instrument for measuring high temperatures, esp by measuring the brightness (optical pyrometer) or total quantity (radiation pyrometer) of the radiation produced by the source. Other […]
[pahy-ruh-met-l-ur-jee] /ˌpaɪ rəˈmɛt lˌɜr dʒi/ noun 1. the process or technique of refining ores with heat so as to accelerate chemical reactions or to melt the metallic or nonmetallic content. /ˌpaɪrəʊmɛˈtælədʒɪ; -ˈmɛtəˌlɜːdʒɪ/ noun 1. the branch of metallurgy involving processes performed at high temperatures, including sintering, roasting, smelting, casting, refining, alloying, and heat treatment
noun 1. (in a kiln) a ball of material that indicates by changing color that a certain temperature has been reached.