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(word root) straight
Examples of words with the root ortho-: orthodontia



[From ortho-.]


(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]
References in periodicals archive ?
Plaintiffs say Ortho McNeil has failed to conduct any meaningful surveillance.
Last month, the manufacturer, Ortho Women's Health and Urology, announced preliminary results of the two studies, which compare thrombotic event rates in women on Ortho Evra and women on an oral contraceptive pill containing norgestimate with 35 mcg of ethinyl estradiol.
The target will be operated at 17 K where the equilibrium ortho to para hydrogen ratio is 0.
ws, did not resemble the standard Ortho Evra patch.
Ortho Kinematics is a privately held diagnostic technology company, focused on spine imaging informatics and committed to the idea that spine motion matters.
In a recent survey of 120 Ortho Personal Pak users, half of respondents said they were more likely to take their birth control pill on time as a result of using the compacts.
In late 1990, the FDA asked the Justice Department to investigate whether Ortho had engaged in an illegal promotion of Retin-A for an unapproved use.
Ten women filed a lawsuit against the makers of the Ortho Evra contraceptive patch, alleging they were not adequately warned of the product's risks.
The new Ortho Dialpak is a significant advance in birth control pill packaging," says Barbara Somma, Ortho-McNeil's senior director of marketing services.