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reredos

(Encyclopedia)reredos rērˈdŏs [key], ornamented wall or screen that rises behind the high altar of a church, forming a background for it. It may be placed against the apse wall at the extreme end or directly beh...

digital-to-analog conversion

(Encyclopedia)digital-to-analog or D/A conversion, the process of changing discrete digital data into a continuously varying signal in relation to a standard or reference. There are two types of converters: electro...

tympanum

(Encyclopedia)CE5 Tympanum (west pediment, temple of Aphaia at Aegina) tympanum tĭmˈpənəm [key]. In architecture, the triangular space of a pediment, or low-pitched gable, above a portico, door, or window. ...

porphyry, igneous rock

(Encyclopedia)porphyry pôrˈfərē [key], igneous rock composed of large, conspicuous crystals (phenocrysts) and a groundmass in which the phenocrysts are embedded. Some authorities consider the expression “porp...

baldness

(Encyclopedia)baldness, thinning or loss of hair as a result of illness, functional disorder, or hereditary disposition; also known as alopecia. Male pattern baldness, a genetic trait, is the most common cause of b...

basketry

(Encyclopedia)basketry, art of weaving or coiling and sewing flexible materials to form vessels or other commodities. The materials used include twigs, roots, strips of hide, splints, osier willows, bamboo splits, ...

phlebitis

(Encyclopedia)phlebitis fləbīˈtĭs [key], inflammation of a vein. Phlebitis is almost always accompanied by a blood clot, or thrombus, in the affected vein, a condition known as thrombophlebitis (see thrombosis)...

set, in mathematics

(Encyclopedia)CE5 Union and intersection of sets A and B: The union of A and B, A∪B, contains all members belonging to either A or B. The intersection of A and B, A∩B, contains all members common to both A a...

torsion balance

(Encyclopedia)torsion balance, instrument used to measure small forces. It is based on the principle that a wire or thread resists twisting with a force that is proportional to the stress. The torsion balance consi...

crochet work

(Encyclopedia)crochet work krōshāˈ [key], form of knitting done with a hook, by means of which loops of thread or yarn are drawn through other, preceding loops. Crochet stitches are all based on the chain or sin...