n. pl. apparatus or ap·pa·rat·us·es 1. a. An appliance or device for a particular purpose: an x-ray apparatus. b. An integrated group of materials or devices used for a particular purpose: dental apparatus. See Synonyms at equipment. 2. a. The totality of means by which a designated function is performed or a specific task executed, as in a system of government. b. A political organization or an underground political movement. Also called apparat. 3. Physiology A group or system of organs that collectively perform a specific function or process: the respiratory apparatus; the digestive apparatus. 4. The critical and source material, usually including notes and a glossary, that accompanies a scholarly edition of a text. [Latin apparātus, preparation, from past participle of apparāre, to prepare : ad-, ad- + parāre, to prepare; see perə-1 in the Appendix of Indo-European roots.] |
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