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(word root) straight
Examples of words with the root ortho-: orthodontia
Abused, Confused, & Misused Words by Mary Embree Copyright © 2007, 2013 by Mary Embree



[From ortho-.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(ˈɔr θoʊ)

pertaining to or occupying two adjacent positions in the benzene ring. Compare meta, para 2.
[1875–80; independent use of ortho-]


1. a combining form meaning “straight,” “upright,” “right,” “correct”: orthodontics; orthopedic.
a. a combining form used in the name of the most hydrated acid in a given series: orthoboric acid. Compare meta- (def. 2a), pyro- (def. 2a).
b. a combining form used in the names of benzene derivatives in which the substituting group occupies the ortho position in the benzene ring.
Also, esp. before a vowel, orth-.
[< Greek, comb. form of orthós straight, upright, correct]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
Under the terms of the MTA, a formulation of the Partner's commercial product will be evaluated for its properties when used in conjunction with Ortho's OrthoR product.
This is in contrast to our findings as we found that Ortho Organizers archwires (Oval Arch Form and Standard Form) have higher frequency as best fit archwire and they are more compatible with mandibular arch form of 34% and 27% of the patients respectively.
GHP Specialty Care AB (GHP) (STO:GHP), a health care provider that operates specialist clinics in a select number of diagnostic areas, announced on Monday, that effective January 2019, GHP Ortho Centre Stockholm is expanding its outpatient business in new central premises at Storangsvagen 10, Gardet, in Stockholm.
Ortho Dermatologics, a Bausch Health company, is one of the largest prescription dermatology businesses in the world dedicated to helping patients in the treatment of a range of therapeutic areas, including psoriasis, actinic keratosis, acne, atopic dermatitis and other dermatoses.
New York-based private equity firm The Carlyle Group, which acquired Ortho from Johnson & Johnson for $4 billion in 2014, reportedly hired Goldman Sachs, JPMorgan Chase and Barclays in late 2017 to explore an IPO or sale.
After scanning the upper and lower arches as well as the bite of the patient, the scans can be sent directly to Ortho Caps for the designing and manufacturing of orthocaps aligners, it added.
Ortho makes devices that test for a variety of diseases, conditions, and substances.
(NYSE: ZBH) (SIX: ZBH) has completed the acquisition of Colorado-based Ortho Transmission, the company said.
: Summary: The antioxidant activity of ortho and meta substituted ferulic acid derivatives have been investigated in the gas phase and water.
Dan Rabish has been hired as director of business development for Ortho Molecular Products, Chicago, IL.