# tri-, tre-

#### (Greek > Latin: a numerical prefix meaning, three, thrice, threefold; triple; a word element for number 3)

triglot

Pertaining to, involving, or containing three languages; such as, a triglot dictionary.

triglyph, triglyphic

1. An ornament in the frieze of the Doric order, repeated at equal intervals.

Each triglyph consists of a rectangular tablet, slightly projecting, and divided nearly to the top by two parallel and perpendicular gutters, or channels, called *glyphs*, into three parts, or spaces, called *femora*.

A half channel, or glyph, is also cut upon each of the perpendicular edges of the tablet.

2. An ornament in a Doric frieze, consisting of a projecting block having on its face two parallel vertical glyphs or grooves and two half grooves or*chamfers*(furrows or grooves) on either vertical end, which separates the*metopes*(spaces between two triglyphs on a Doric frieze).
triglyphal

A reference to a member or ornament in the Doric order, consisting of a block or tablet with three vertical grooves or glyphs (strictly, two whole grooves, and a half-groove on each side), repeated at regular intervals along the frieze, usually one over each column, and one or two between every two columns.

trigon

1. A figure having three angles and three sides; a triangle.

2. A set of three signs of the zodiac, distant 120 degrees from each other, as if at the angles of an equilateral triangle.

2. A set of three signs of the zodiac, distant 120 degrees from each other, as if at the angles of an equilateral triangle.

trigonal

Triangular; related to a

*trigonum*.
trigone

1. Any triangular area.

2. The first three dominant cusps (

2. The first three dominant cusps (

*protocone, paracone,*and*metacone*), taken collectively, of an upper molar tooth.
trigoneutic

In entomology, having three broods a year.

trigonid

The first three dominant cusps, taken collectively, of a lower molar tooth.

trigonitis

1. Inflammation of the urinary bladder.

2. Inflammation localized at the bladder trigone (trigonum vesicae), producing an edematous (swollen with an excessive accumulation of fluid) and sometimes bulbous (bulb) appearance of the mucosa of the trigone; also known as

2. Inflammation localized at the bladder trigone (trigonum vesicae), producing an edematous (swollen with an excessive accumulation of fluid) and sometimes bulbous (bulb) appearance of the mucosa of the trigone; also known as

*collitis*.
trigonometry

That branch of mathematics that deals with the measurement of the sides and angles of triangles, particularly with certain functions of their angles or of angles in general (the sine, cosine, tangent, cotangent, secant, and cosecant), and hence with these functions as applied to abstract quantities; thus including the theory of triangles, of angles, and of (elementary) singly periodic functions.

trigonum (s), trigona (pl)

1. Any triangular area.

2. Etymology: Greek > Latin

2. Etymology: Greek > Latin

*trigonon*, "a triangle".
trigram

An inscription of three letters.

trigraph

A combination of three letters denoting a simple sound; such as,

*eau*in**plateau**, or*igh*in**high**or**thigh**.
trigynous

In botany, having three pistils.

trihedral

Of a solid figure or body having three sides or faces (in addition to the base or ends); bounded laterally by three surfaces; triangular in section.