bi-, bin-, bino-, bis-

(Latin: two, twice, double, twofold; a number; it normally functions as a prefix)

This bi- is used before s, c, or a vowel. Don't confuse this bi- with another one which means "life".

All words except biennial referring to periods of time and prefixed by bi- are potentially ambiguous. Since bi- can be taken to mean either "twice each" or "every two", a word like "biweekly" can be understood as "twice each week" or "every two weeks".

bimillennium
bimonthly
bimorphemic (adjective) (not comparable)
Pertaining to that which consists of two morphemes or the smallest meaningful elements of speech or writing: A few bimorphemic words include, waited, rays, and dogs.
binary
1. Made up of two parts or things; two fold; double.
2. Designating or of a number system in which the base used is two, each number being expressed in powers of two by using only two digits; specifically, "0" and "1".
3. Designating or of a musical form consisting of two main sections.
4. In chemistry, composed of two elements or radicals, or of one element and one radical [binary compounds].
binary code
A way of representing text or computer processor instructions by the use of the binary number system's two-binary digits 0 and 1.

A binary system in general is any system that allows just two choices; such as, a switch in an electronic system or a simple true or false test.

binary digit
A character used with computers to represent one of the two digits; either 0 or 1, in the binary number system.
binasal hemianopia
Blindness in the nasal half of the visual field in each eye.
binate
In botany, occurring in pairs as with binate leaves.
binaural, binaurally
1. Having two ears.
2. Involving the use of both ears.
3. Designating sound reproduction or transmission in which at least two sources of sounds are used to give a stereophonic effect.
Take a tip from nature: your ears aren't made to shut, but your mouth is!
—E.C. McKenzie
binauricular
binocle
A dioptric telescope, fitted with two tubes joining, so as to enable a person to view an object with both eyes at once; a double-barreled field glass or an opera glass.
binocular
1. With both eyes, as in binocular vision.
2. With two eyepieces, as in a binocular microscope.
3. Involving or using both eyes, or relating to vision using both eyes.

As stated above, binoculars are field glasses adapted to the use of both eyes, in contrast with the telescope, which is a monocular instrument.

binocular vision (s) (noun), binocular visions (pl)
The simultaneous use of both eyes, resulting in seeing which incorporates images with depth perception.
binocularly, binocularity
1. Relating to, used by, or involving both eyes at the same time; such as, binocular vision.
2. Having two eyes arranged to produce stereoscopic vision.

An optical device, such as a pair of field glasses or opera glasses, designed for simultaneous use by both eyes and consisting of two small telescopes joined with a single focusing device.

binoculus
The two eyes regarded as a functional unit.