theorbo

[Ital. tiorba; Fr. théor be.] Music: An old stringed instrument resembling the lute in form or tone. It had two necks, to the longest of which the ba strings were attached. It was employed for accompanying voices, and was in great favor during the seventeenth century. It differed from the lute in the po e ion of its two necks, whence it is sometimes called Cithara bijuga. The strings were usually single in the theorbo, and when double, or tuned in octaves or in unison with the base or treble notes, the instrument was called the Arch-lute, or Chit tar one. the-ô-rěm, subst. [Lat. theorem a, from Gr. theōrēma =a spectacle, hence Theorbo. a subject for contemplation, a principle, a theorem, from theōrō =to look at, to behold, to view; theōrosa spectator; theaomai , theōmai =to see, to view; Fr. théorème ; Sp. & Ital. teorema .] 1. Geom.: A proposition to be proved; a statement of a principle to be demonstrated; that is, the truth of which is required to be made evident by a course of reasoning, called a demonstration. In the synthetical method of investigation, which is that for the most part employed in geometry, it is usual to state the principle to be proved before commencing the demonstration, which proceeds by regular course of argumentation to the final conclusion, confirmatory of the principle enunciated. The principle being proved, it may properly be employed as a premi in the deduction of new truths. The principle, as enunciated before the demonstration, is the theorem; its statement after demonstration constitutes a rule or formula, according as the statement is made in ordinary or in algebraic language. A theorem differs from a problem in this, that the latter is a statement of something to be done, the former of something to be proved. 2. Alg . & Anal .: Something used to denote a rule, epecially when that rule is expre ed by symbols or for mule; as, the binomial theorem . *3. A speculative truth; a position laid down as an acknowledged truth; that which is considered and established as a principle. "Questionle he (Soloman) was himself most conversant therein [theology]; for proof whereof he did leave so many excellent theorems and precepts of divinity to us." -Barrow: Sermons, vol. iii., ser. 22. IMG:content-0991.png:[blocks in formation] theory (1) Negative theorem: A theorem which expre es the impo ibility of any a ertion. (2) Particular theorem: A theorem which extends only to a particular quantity. (3) Universal theorem : A theorem which extends to any quantity without restriction. thê-ô-rěm, v. t. [THEOREM, s.] To reduce to or formulate into a theorem.