orth-

combining form
variants: or ortho-

Definition of orth-

1 : straight : upright : vertical
  • orthograde
2 : perpendicular
  • orthorhombic
3 : correct : corrective
  • orthodontia
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

Origin and Etymology of orth-

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


Medical Dictionary

orth-

prefix
variants: or ortho-

medical Definition of orth-

1 : hydrated or hydroxylated to the highest degree
  • orthophosphoric acid
2 : involving substitution at or characterized by or having the relationship of two neighboring positions in the benzene ring abbreviation o-
  • ortho-xylene or o-xylene
— compare meta- 2, para- 2

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