Ortho (from the Greek word ὀρθός meaning "straight" or "correct") may refer to:

In science

  • An arene substitution pattern in which two substituents occupy adjacent positions on an aromatic ring
  • Chlordane an organochlorine compound that was used as a pesticide
  • Ortho Mode Transducer, is a waveguide component
  • An Orthochromatic spectrum is any spectrum of light devoid of red

In cartography

  • Orthophotography, aerial photography

In mathematics

  • Orthogonality
  • Orthonormality

In computer science

  • Orthographic projection, a means of representing a three-dimensional (3D) object in two dimensions (2D).

In medicine

  • Orthomyxovirus - family of viruses to which influenza (causative agent of the flu) belongs
  • Orthodontics, a specialty of dentistry concerned with the study and treatment of malocclusions
  • Orthopedic, the study of the musculoskeletal system.
  • Ortho-DOT, a psychedelic drug
  • Ortho-cept and Ortho Tri-cyclen, kinds of oral contraceptive drug

In theology

  • Orthodoxy, right (correct) belief
  • Orthopraxy, right (correct) action


  • Ortho Pharmaceutical, which merged into Ortho-McNeil Pharmaceutical before being bought by Johnson & Johnson
  • Ortho-Clinical Diagnostics, another subsidiary of Johnson & Johnson

Other articles related to "ortho":

The Red Box - The Unfamiliar Word
... Ortho-cousin, chapter 1 ... Frost's familiarity with so strange a term as 'ortho-cousin,' strictly a word for an anthropologist, though it leaves room for various speculations ... Ortho-cousins are those whose parents are of the same sex — the children of two brothers or of two sisters whereas cross-cousins are those whose parents are brother and sister ...
Ortho-Mc Neil Pharmaceutical
... The company was formed from the merger of Ortho Pharmaceutical and McNeil Pharmaceutical in 1993 ... Ortho-McNeil and Janssen have been placed in the Ortho-McNeil-Janssen group within Johnson Johnson ... Ortho-McNeil is headquartered in Raritan, New Jersey ...
Cyclopropenylidene - Spectroscopy
... These ortho and para forms exist in a 31 ratio and should be thought of as distinct molecules ... Although the ortho and para forms look identical chemically, the energy levels are different, meaning that the molecules have different spectroscopic transitions ... are the 110 to 101 transition at 18343 MHz and the 212 to 101 transition at 85338 MHz of ortho c-C3H2 ...
... ortho-Vanillin (2-Hydroxy-3-methoxybenzaldehyde) is an organic solid present in the extracts and essential oils of many plants ... ortho-Vanillin, a compound of the formula C8H8O3, is distinctly different from its more prevalent isomer, vanillin ... The "ortho-" prefix refers the to position of the compound’s hydroxyl moiety, which is found in the para-position in vanillin ...
Silver Acetate - Reactions - Direct ortho-arylation
... acetate is a useful reagent for direct ortho-arylation (to install two adjacent substituents on an aromatic ring) for of benzylamines and N-methylbenzylamines ... This reaction is shorter than previous ortho-arylation methods ...