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ortho
[ awr-thoh ]
/ ˈɔr θoʊ /
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Definition of ortho
adjective Chemistry.
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Origin of ortho
First recorded in 1875–80; independent use of ortho-
Words nearby ortho
Other definitions for ortho (2 of 2)
ortho-
a combining form occurring in loanwords from Greek, where it meant “straight,” “upright,” “right,” “correct” (orthodox) and on this model used in the formation of compound words (orthopedic).
Chemistry.
- a combining form used in the name of that acid in a given series of acids that contains the most water (orthoboric acid).Compare meta-, pyro-.
- a combining form used in the names of the salts of these acids: if the acid ends in -ic, the corresponding salt ends in -ate (orthoboric acid (H3BO3) and potassium orthoborate (K3BO3)); if the acid ends in -ous, the corresponding salt ends in -ite (orthoantimonous acid (H3SbO3) and potassium orthoantimonite (K3SbO3)).
Also especially before a vowel, orth-.
Origin of ortho-
<Greek, combining form of orthós straight, upright, correct
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
How to use ortho in a sentence
British Dictionary definitions for ortho
ortho-
before a vowel orth-
combining form
straight or uprightorthotropous
perpendicular or at right anglesorthoclastic
correct or rightorthodontics; orthodox; orthography; orthoptics
(often in italics) denoting an organic compound containing a benzene ring with substituents attached to adjacent carbon atoms (the 1,2- positions)orthodinitrobenzene Abbreviation: o- Compare oarsman Compare oarsman
denoting an oxyacid regarded as the highest hydrated form of the anhydride or a salt of such an acidorthophosphoric acid See meta- (def. 6)
denoting a diatomic substance in which the spins of the two atoms are parallelorthohydrogen See para- 1 (def. 8)
Word Origin for ortho-
from Greek orthos straight, right, upright
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
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