tri-, tre-

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

tricrotism
The condition of having three waves, a reference to the pulse.
tricuspid
An organ or a part, especially a tooth, having three cusps (points).
tricycle (s) (noun), tricycles (pl)
1. A velocipede with three wheels, one in the front and two in the rear.
2. A vehicle, used especially now by small children, that has three wheels, one at the front and two a the back, and is usually propelled by pedals.
tridactyl, tridactyle, tridactylous
1. Having three toes, claws, or similar parts on each limb.
2. Having three digits, either fingers or toes; also, tridigitate.
tridactyly
Having three digits on a limb, as with some birds and ancestors of the horse; such as, Protohippus and Hipparion.
trident
1. An instrument or weapon with three prongs; especially, a three-pronged fish-spear or sceptre as the attribute of the sea-god Poseidon or Neptune, also figured as borne by Britannia.
2. A three-pronged spear used by the retiarius in ancient Roman gladiatorial combats.
3. Applied to something resembling a trident in shape or configuration, as a three-pronged fork, a piece of land with three promontories.
tridentate
Three-toothed, three-pronged.
tridermic
Relating to or derived from the three primary germ layers of the embryo: ectoderm, endoderm, and mesoderm.
tridigital
Having three digits (fingers or toes).
tridigitate, tridactylous
Having three fingers or three toes on one hand or foot.
tridimensional
Having or exhibiting three dimensions, as a solid body.
tridiurnal (adjective) (not comparable)
1. Consisting of three days.
2. Occurring three times a day.
triennial
1. Existing or lasting for three years, three-years; changed every three years.
2. Recurring every three years.
3. A commemoration or celebration of an event that occurred three years earlier; a third anniversary.
triennially
1. Referring to a third anniversary.
2. Descriptive of something which appears or occurs every three years.
3. Referring to a period of three years; triennium.
triennium
A space or period of three years.

Cross references of word families that are related, partially or totally, to: "three, third": terce-; terti-; trigono-; trito-.