Standard Lemma guide

bi-

prefix · 13 senses · updated from the 2026-07-25 local source snapshot

Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.

Sound

Pronunciation

Each Play button uses your device's default local English voice, or a natural local fallback. The selected voice name appears after playback. This is synthesized speech, not a source recording.

  • /baɪ-/
  • rare: /bɪ-/
  • US: Recorded audio is listed in the source snapshot.

1

prefix

Meaning 1

Two in number.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

  • biarticular
  • biaxial
  • bicoloured

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

prefix

Meaning 2

Having or possessing two of the root word's quality.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

  • biangular
  • biantheriferous
  • bicardial
  • bikont

Meaning relationships

Synonyms: none provided

Antonyms: none provided

3

prefix

Meaning 3

Both: referring to two as a set.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

  • biacetabular
  • biallelic
  • bicaval

Meaning relationships

Synonyms: none provided

Antonyms: none provided

4

prefix

Meaning 4

Being different in two ways with respect to the root.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

  • biadjoint
  • biaffine
  • biclonal

Meaning relationships

Synonyms: none provided

Antonyms: none provided

5

prefix

Meaning 5

Forked, divided by two, halved; (chemistry, proscribed) half

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

  • bifurcate
  • bicapitate
  • bicarinate

Meaning relationships

Synonyms: none provided

Antonyms: none provided

6

prefix

Meaning 6

Double, twofold.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

  • bialgebroid
  • bifarious
  • biarticulated

Meaning relationships

Synonyms: none provided

Antonyms: none provided

7

prefix

Meaning 7

Bisexual, relating to bisexuality.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

  • bicentric
  • biphobia
  • biromantic

Meaning relationships

Synonyms: none provided

Antonyms: none provided

8

prefix

Meaning 8

Bilateral, on both sides of the body.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Topics: anatomy, medicine, sciences

Examples

  • biconcave
  • biballism

Meaning relationships

Synonyms: none provided

Antonyms: none provided

9

prefix

Meaning 9

Twice.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

  • biannual
  • biconjugate

Meaning relationships

Synonyms: none provided

Antonyms: none provided

10

prefix

Meaning 10

Every two; a rate of once every two.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

  • biannual
  • bicentennial

Meaning relationships

Synonyms: none provided

Antonyms: none provided

11

prefix

Meaning 11

A pair of; composed of two.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Examples

  • bibrow
  • bicomplex

Meaning relationships

Synonyms: none provided

Antonyms: none provided

12

prefix

Meaning 12

Used for the digit two to form systematic element names of elements whose existence has been predicted, and which have not yet been given a trivial name.

Definition source: English Wiktionary via Wiktextract

Usage: morpheme

Topics: chemistry, natural-sciences, physical-sciences

Examples

  • un- (“1”) + bi- (“2”) + un- (“1”) + -ium (element suffix) → unbiunium (“element 121”)

Meaning relationships

Synonyms: none provided

Antonyms: none provided

13

prefix

Meaning 13

Alternative form of bio-.

Definition source: English Wiktionary via Wiktextract

Usage: alt-of, alternative, before-vowel, morpheme

Examples

  • biont

Meaning relationships

Synonyms: none provided

Antonyms: none provided

History

Etymology

PIE word *dwóh1 Borrowed from Latin bi-, from Proto-Italic *dwi-, from Proto-Indo-European *dwi-. Doublet of twi- and di-.

From Ancient Greek βίος (bíos, “life”).

Across languages

Translations

41 source translations are retained for this English entry.

  • Bengali: দুই (dui) — two-
  • Catalan: bi- — two-
  • Chinese Mandarin: 雙 /双 (shuāng) — two-
  • Czech: bi- — two-
  • Dutch: bi- — two-
  • Dutch: twee- — two-
  • Dutch: dubbel- — two-
  • French: bi- — two-
  • Galician: bi- — two-
  • Georgian: ბი- (bi-) — two-
  • Georgian: ორ- (or-) — two-
  • German: bi- — two-
  • German: zwei- — two-
  • Greek: δι- (di-) — two-
  • Hebrew: דו־ — two-
  • Hindi: द्वि- (dvi-) — two-
  • Hungarian: bi- — two-
  • Ido: bi- — two-
  • Indonesian: dwi- — two-
  • Indonesian: bi- — two-
  • Irish: dé- — two-
  • Italian: bi- — two-
  • Japanese: 双 (sō) — two-
  • Malay: dwi- — two-
  • Malay: bi- — two-
  • Manx: daa- — two-
  • Māori: rua — two-
  • Polish: bi- — two-
  • Polish: dwu- — two-
  • Portuguese: bi- — two-
  • Punjabi: ਦੁ- (du-) — two-
  • Russian: двух- (dvux-) — two-
  • Russian: дву- (dvu-) — two-
  • Russian: би- (bi-) — two-
  • Spanish: bi- — two-
  • Spanish: bis- — two-
  • Spanish: biz- — two-
  • Swedish: bi- — two-
  • Ukrainian: бі- (bi-) — two-
  • Ukrainian: дво- (dvo-) — two-
  • Ukrainian: двох- (dvox-) — two-