BI- Definition & Meaning | Dictionary.com

bi-

a combining form meaning “twice,” “two,” used in the formation of compound words:
bifacial; bifarious.

bi-

variant of bio-, especially before a vowel:
biopsy.

[ bahy ]

Phonetic (Standard)IPA

adjective

plural bis, bi's.

Slang. bisexual.

⁴

Symbol, Chemistry.

bismuth.

⁵

abbreviation for

plural BI's.

plural BIs built-in.
business intelligence.

the chemical symbol for

bismuth

/ ��ɪ /

adjective

slang.
short for bisexual bisexual

bi-

combining_form

two; having two
bifocal
occurring every two; lasting for two
biennial
on both sides, surfaces, directions, etc
bilateral
occurring twice during
biweekly
1. denoting an organic compound containing two identical cyclic hydrocarbon systems
  biphenyl
2. (rare in technical usage) indicating an acid salt of a dibasic acid
  sodium bicarbonate
3. (not in technical usage) equivalent of di- 1

bi-

⁴

combining_form

a variant of bio-

⁵

the internet domain name for

Burundi

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Confusables Note

All words except biennial referring to periods of time and prefixed by bi- ¹ 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.” To avoid confusion, it is better to use the prefix semi- to mean “twice each” ( semiannual; semimonthly; semiweekly ) or the phrase twice a or twice each ( twice a month; twice a week; twice each year ), and for the other sense to use the phrase every two ( every two months; every two weeks; every two years ).

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�y��vlog History and Origins

Origin of bi-¹

< Latin, combining form of bis; twice

Origin of bi-²

By shortening

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�y��vlog History and Origins

Origin of bi-¹

from Latin, from bis twice

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�y��vlogs That Use Bi-

What does bi- mean?

Bi- is a combining form used like a prefix, and it means “two” or “twice.” It is often used in scientific terms, but it crops up in everyday language as well.

Bi- comes from Latin bis, meaning “twice, doubly.” The Greek equivalent of this combining form is di-, as in diacid.

What are variants of bi-?

Bi- is related to the combining form bin– and is used with some words or word elements beginning with vowels. These two forms have similar origins, and for that reason, the difference between the two is a small yet important nuance: bi- often means “twice,” while bin- typically means “double.”

Want to know more? Read our �y��vlogs That Use bin- article.

Examples of bi-

An example of a word you may have encountered that features bi- ��biannual, which can mean either “occurring twice a year” or “occurring every two years.”

Confused? You’re not alone! When it comes to indicating dates on the calendar, bi- likes to have it both ways, as it were. Learn some tips on using biannual and other tricky terms like biweekly here.

We know bi- means “twice,” but what about the -annual portion of the word? You guessed it: -annual means “yearly,” from Latin annuālis. Biannual literally translates to “twice yearly.”

What are some words that use the combining form bi-?

The following words use the equivalent forms of bi- in Latin:

What are some other forms that bi- may be commonly confused with?

There are many words that begin with the letters bi-, such as bias, that do not use the combining form bi- to denote “two.” Learn what words like bias and bilk mean at our entries for these words.

Break it down!

Humans, like many animals, are considered bipeds. The combining form -ped means “(having a) foot.” With this in mind, what is the literal meaning of biped?

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