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".

bifurgate
To divide (or fork) into two branches.
bigamist
Italian for thick fog, big-a-mist.
bigamist
1. A person who commits bigamy or someone who is married illegally to two people simultaneously.
2. Said to be someone who demonstrates that "two rites make a wrong" and an action by someone who is participating in "double jeopardy".
bigamous
Involved in or constituting an illegal marriage made when an existing marriage is still valid.
bigamously
bigamy
1. Marriage with a second wife or husband during the lifetime of the first; the crime of having two wives or husbands at the same time.
2. The crime of marrying someone while being legally married to someone else.
3. In law, the criminal offense of willfully and knowingly contracting a second marriage (or going through the form of a second marriage) while the first marriage, to the knowledge of the offender, is still subsisting and undissolved. The state of a man who has two wives, or of a woman who has two husbands, living at the same time.
4. Bigamus seu trigamus, etc., est qui diversis temporibus et successive duas seu tres uxores habuit (A bigamus or trigamus, etc., is one who at different times and successively has married two or three wives).
bigamy (lexicomedy)
Having one spouse too many and there are some who believe that monogamy is the same.
bigamy, monogamy, polygamy
bigamy (BIG uh mee) (noun)
The act of being married to two spouses at the same time: The women were horrified to realize they were the victims of bigamy when they discovered they were both married to the same man!
monogamy (muh NAHG uh mee) (noun)
Marriage to only one person at a time: In many cultures, monogamy is the typical practice of marriage with just one spouse at a time.
polygamy (puh LIG uh mee) (noun)
Plural marriage; having more than one wife or husband at the same time: Occasionally there are articles in the newspapers about obscure religious groups that practice polygamy; for example, one man with thirteen wives.

Bigamy is proof that two rites make a wrong.

—Evan Esar

Monogamy is a monopoly.

—Anonymous

The media headlines about marriage lifestyles were rampant, exclaiming that those who practiced either bigamy or polygamy were carrying things too far. There was no mention about the success of monogamy.

bigeminal
Existing or arranged in two pairs; specifically in medicine, applied to the corpora quadrigemina of the brain, lying beneath the cerebral hemispheres.
biglandular
bihourly (adjecrive) (not comparable)
Regarding something taking place every two hours: Dr. Smart told Jane that she should take her medicine bihourly, except during the night, and for three days in a row in order to cure her ailment.
bilabial
bilateral
1. In politics, involving or carried out by two groups; especially, the political representatives of two countries.
2. Relating to or affecting both of two sides; bilateralism, bilaterally.
3. Arranged symmetrically on opposite sides of an axis.
bilateralism
bilaterally