Definify.com

Webster 1913 Edition

Ortho-

Or′tho-

(ôr′thō̍-)
p
ref.
[Gr.
ὀρθόσ
straight; akin to Skr.
ūrdhva
upright,
vṛdh
to grow, to cause to grow.]
1.
A combining form signifying
straight
,
right
,
upright
,
correct
,
regular
;
as,
ortho
dromy,
ortho
diagonal,
ortho
dox,
ortho
graphic
.
2.
(Chem.)
A combining form (also used adjectively)
,
designating:
(a)
(Inorganic 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,
ortho
phosphoric acid
. Cf.
Normal
.
(b)
(Organic 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
.
☞ In the graphic representation of the benzene nucleus (see
Benzene nucleus
, under
Benzene
), provisionally adopted, any substance exhibiting double substitution in adjacent and contiguous carbon atoms, as 1 & 2, 3 & 4, 4 & 5, etc., is designated by
ortho-
; as,
ortho
xylene; any substance exhibiting substitution of two carbon atoms with one intervening, as 1 & 3, 2 & 4, 3 & 5, 4 & 6, etc., by meta-; as, resorcin or metaxylene; any substance exhibiting substitution in opposite parts, as 1 & 4, 2 & 5, 3 & 6, by para-; as, hydroquinone or paraxylene.

Definition 2024

ortho-

ortho-

See also: ortho

English

Prefix

ortho-

  1. straight, right, proper
  2. (chemistry) Having an extra proportion of water
  3. (chemistry) in isomeric benzene derivatives, having the two substituents in adjacent positions (compare meta- and para-)
  4. (physics) of any molecule of the form X2 in which the two nuclei have parallel spin

Derived terms

<a class='CategoryTreeLabel CategoryTreeLabelNs14 CategoryTreeLabelCategory' href='/wiki/Category:English_words_prefixed_with_ortho-'>English words prefixed with ortho-</a>

French

Etymology

Ancient Greek ὀρθός ‎(orthós).

Prefix

ortho-

  1. right

Derived terms

Etymology

Ancient Greek ὀρθός ‎(orthós).

Similar Results