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combining form

Definition of orth-

  1. 1 :  straight :  upright :  vertical <orthograde>

  2. 2 :  perpendicular <orthorhombic>

  3. 3 :  correct :  corrective <orthodontia>

  4. 4 a :  hydrated or hydroxylated to the highest degree <orthophosphoric acid> b :  involving substitution at or characterized by or having the relationship of two neighboring positions in the benzene ring <ortho-xylene>

Variants of orth-

or ortho-

Origin of orth-

Greek, from orthos straight, right, true; akin to Sanskrit ūrdhva high, upright

Learn More about orth-

  1. Medical Dictionary: Definition of "orth-"

Seen and Heard

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to dishevel or rumple

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