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".

biphasic
Having two distinct phases.
biphasic sleep
1. A long sleep period at night and a "nap" in the afternoon.
2. Having two distinct phases of sleep.
biphonemic
Constituting, consisting of, or standing for two phonemes.
biplane
bipod
A two-legged support or structure; especially, one for a light machine-gun.
bipolar
bipolar electrocardiogram (s) (noun), bipolar electrocardiograms (pl)
An electronic instrument which obtains information by recording the differences in the voltages of two electrodes at different sites or parts of the surfaces of a body.
bipolar electrocautery (s) (noun), bipolar electrocauteries (pl)
An surgical dissection in which both active and return electrodes are incorporated into a single hand-held instrument, so that the current passes between the tips of the two electrodes and affects only a small amount of tissue.
bipolar needle electron (s) (noun), bipolar needle electrons (pl)
An electrode consisting of two insulated wires inside a single cylinder with neither one acting as the reference electrode.

Variations in voltage can be noted between the areas that the wires touch.

bipolar stimulating electrode (s) (noun), bipolar stimulating electrodes (pl)
An electrode which has the two terminals attached together and near each other.
bipolarity
biquarterly
biracial
biradial
biscuit
1. An unsweetened bread in the shape of a small cake, made with a generous amount of shortening and leavened with baking powder or baking soda instead of yeast.
2. In British English, a biscuit is a small flat cake that is crisp and usually sweet; while the usual American word is "cookie".
3. Clay or porcelain that has been fired once but not glazed.