ORTHO

Noun

ortho (countable and uncountable, plural orthos)

(countable, chemistry) An isomer of a benzene derivative having two substituents adjacent on the ring.

(countable, astronomy) A certain type of flat eyepiece.

(countable, photography, dated) An orthochromatic plate.

(countable, imaging) An orthophoto.

(uncountable, medicine) Orthopedics.

Anagrams

• thoro

Source: Wiktionary

Or"tho-. Etym: [Gr. upright, vrdh to grow, to cause to grow.]

1. A combining form signifying straight, right, upright, correct, regular; as, orthodromy, orthodiagonal, orthodox, orthographic.

2. (Chem.)

Definition: 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, orthophosphoric acid. Cf. Normal. (b) (Organic Chem.)

Definition: 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.

Note: 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, orthoxylene; 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.

Source: Webster’s Unabridged Dictionary 1913 Edition