• Webster's Revised Unabridged Dictionary
    • Ortho- (Chem) Connection with, or affinity to, one variety of isomerism, characteristic of the benzene compounds; -- contrasted with meta- or para-; as, the ortho position; hence, designating any substance showing such isomerism; as, an ortho compound.
    • Ortho- A combining form (also used adjectively
    • Ortho- A combining form signifying straight right upright correct regular; as, orthodromy, orthodiagonal, orthodox, orthographic.
    • Ortho- (Chem) The one of several acids of the same element (as the phosphoric acids), which actually occurs with the greatest number of hydroxyl groups; as, orthophosphoric acid. Cf. Normal.
    • ***


Webster's Revised Unabridged Dictionary
Gr. 'orqo`s straight; akin to Skr. ūrdhva, upright, vṛdh, to grow, to cause to grow


In literature:

If they are side by side (called the ortho position) we have an oil with the odor of meadowsweet.
"Creative Chemistry" by Edwin E. Slosson
East Somerville, Franklin Street Ortho., S., 3.29.
"The American Missionary - Volume 52, No. 2, June, 1898" by Various
Ortho-nitro-diazobenzene imide only yields 30%.
"Encyclopaedia Britannica, 11th Edition, Volume 3, Part 1, Slice 1" by Various
Melrose, Ortho., C., Sewing Circle, two bbls.
"The American Missionary -- Volume 54, No. 3, July, 1900" by Various
In his talk on "The Magic of Modern Chemistry," Professor MacTavish demonstrated the separation of para-hydrogen and ortho-hydrogen.
"Astounding Stories, March, 1931" by Various
It is well known that di-ortho-substituted benzoic acids are esterified with difficulty.
"Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 1" by Various
Ortho-cresol, CH3(1).C6H4.OH(2), occurs as sulphate in the urine of the horse.
"Encyclopaedia Britannica, 11th Edition, Volume 7, Slice 6" by Various
This change only occurs when the halogen atom is in the ortho- or para- position to the -N2- group.
"Encyclopaedia Britannica, 11th Edition, Volume 8, Slice 4" by Various
Ortho-nitrophenol, C6H4.OH.NO2(1.2), crystallizes in yellow needles which melt at 45 deg.
"Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 3" by Various
C. By condensing ortho-brombenzyl bromide with sodium, C.L.
"Encyclopaedia Britannica, 11th Edition, Volume 2, Slice 2" by Various
The ortho- and para-nitro-benzoic acids can be obtained by oxidizing ortho-and para-nitro-cinnamic acids.
"Encyclopaedia Britannica, 11th Edition, Volume 3, Slice 6" by Various
Orthos, Bridge of, 172.
"Dumas' Paris" by Francis Miltoun
The enzymes ptyalin and emulsin convert it into glucose and saligenin, ortho-oxybenzylalcohol, HO.C6H4.CH2OH.
"Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 2" by Various
When warmed with aniline it yields anilido-aposafranine, which may also be obtained by the direct oxidation of ortho-aminodiphenylamine.
"Encyclopaedia Britannica, 11th Edition, Volume 14, Slice 5" by Various

In news:

Sanford- Burnham , Ortho Team Up on Alzheimer's Treatment.
DISCLOSURE Nurse Dehn is a consultant to Hologic, Inc, Ortho-McNeil-Janssen Pharmaceuticals, Inc, and Graceway Pharmaceuticals, LLC.
LENS DESIGN Dual Geometric Lenses for Hyperopia Ortho-K A new type of ortho-k lens promises to be less complicated and more successful.
A $166,047 fine in 2006, after California regulators found two unregistered products sold under the company's Ortho brand.
Qualitest, Emoquette, oral contraceptive , desogestrel and ethinyl estradiol, Ortho-Cept, generic, birth control, Endo, pharmaceutical, Ortho-McNeil.
Cannerelli / The Post-Standard Fox Holt, CEO of Orthogonal Inc in Ithaca, holds a bottle of Ortho 310 photoresist, a nontoxic material used in the manufacturing of organic electronics.
Registered Nurse -Ortho/Surg PRN (128517) Click Logo To Visit Website.
Orexo Gets $10M Up Front under Respiratory Disease Alliance with Ortho-McNeil and Janssen.
Johnson & Johnson's Centocor Ortho Biotech is launching a psoriasis awareness campaign featuring sufferer Jon Lovitz.
In the meantime, Ortho has received F.D.A.
Registered Nurse -Ortho/ Surg PRN (128517) Click Logo To Visit Website.
Centocor Ortho Biotech Inc Submits Application to FDA Seeking REMICADE® Pediatric Ulcerative Colitis Indication.
New ortho care designed for braces.
Kptm.com Dentist-Approved Ortho Care Designed for Braces.
Tucson News NowDentist-Approved Ortho Care Designed for Braces.

In science:

Note that the ortho-para-states coherence means at the same time the coherence between states with various J (due to the mentioned I − J correlation).
Prototype model for nuclear spin conversion in molecules: The case of "hydrogen"
So the collisions do not initiate direct transitions between ortho- and parastates.
Prototype model for nuclear spin conversion in molecules: The case of "hydrogen"
Co , Cp (So , Sp ) are the BGS specific heats (entropies) of ortho- and parahydrogen, respectively.
Thermodynamical Test of Non Extensive Thermostatistics
The theoretical predictions for the annihilation decay rates for ortho- and parapositronium are summarized in Table 6.
Precision Study of Positronium: Testing Bound State QED Theory
Theory of annihilation decay rate of ortho- and parapositroium (the 1S state).
Precision Study of Positronium: Testing Bound State QED Theory
To perform the direct integral Hilbert space decomposition of Hac spanned by {hpq |N ∋ p > 0, q ∈ N} we choose an ortho-normal cyclic system {Ωm |N ∋ m > 0} in that space, such that Ω1 = N1h10 , where N1 is a normalization constant.
Testing the Master Constraint Programme for Loop Quantum Gravity II. Finite Dimensional Systems
The abundances also only refer to ortho-H2O, while most H2O may be in para form in cold clouds.
The chemistry of high-mass star formation
Reaction 2 has been measured in the lab at low temperatures finding that there is an additional dependence on the ortho/para ratio of H2 (Gerlich et al. 2002).
Cold Dark Clouds: The Initial Conditions for Star Formation
Herschel and SOFIA will be needed to constrain the H2 o/p ratio via observations of ortho- and para-H2D+ in starless cores.
Cold Dark Clouds: The Initial Conditions for Star Formation
E (J (Y )) is the mean vector of J (Y ) and PJ : F c → J (M ) is the ortho-projection on J (M ) de fined on the complement of the set F of focal points of J (M ).
A Nonparametric Approach to 3D Shape Analysis from Digital Camera Images - I. in Memory of W.P. Dayawansa
We can expand ψ in a sum over the ortho-normal eigen -functions of any of these operators.
A Quantum Past
Lorentz transformations, the so-called ‘ortho-chirous Lorentz group ’.
A Judgement on Sinors
For the ortho-H2 , on the contrary, the total nuclear spin is I = 1, since the spins of the two protons are parallel.
Perspectives for detecting cold H2 in outer galactic disks
Only the ortho-H2 is concerned by the ultrafine structure.
Perspectives for detecting cold H2 in outer galactic disks
Normal molecular hydrogen gas contains a mixture of the two varieties, with an ortho-to-para ratio of 3 when the temperature is high with respect to the energy difference of the two fundamental states (171 K).
Perspectives for detecting cold H2 in outer galactic disks