variants: or ortho-

Definition of orth-

1 : straight : upright : vertical orthograde
2 : perpendicular orthorhombic
3 : correct : corrective orthodontia
4a : 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

History and Etymology for orth-

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

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Cite this Entry

“Orth-.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/orth-. Accessed 21 Jan. 2021.

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More Definitions for orth-

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- sense 2, para- sense 2

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