# bra

/ˈbɹɑ/ (US) · /bɹˈɑː/ (UK)

Source: https://englishreference.com/word/bra
Updated: 2026-08-15

## Senses

### 1. clothing

noun · CEFR A2

a piece of underwear that women wear to support their breasts.

For teachers: an undergarment worn by women to support the breasts.

- She bought a new sports bra to wear for her running sessions.
- The fashion industry has seen a shift toward wireless bra designs that prioritise comfort without sacrificing necessary support.

### 2. friend

noun · CEFR C1 · Slang · Informal · Dialect

a very informal way to say 'friend' or 'brother', used when talking to a man.

For teachers: a slang variant of 'bro', used as a familiar term of address for a male peer.

- What's up, bra? I haven't seen you in ages.
- The use of 'bra' as a vocative is common in certain surf and skate subcultures, though it is often perceived as highly informal.

Teaching tip: This is a phonetic spelling of 'bro' common in South African and surfer dialects; learners should be careful as it is identical to the clothing term.

### 3. quantum mechanics

noun · CEFR C2 · Technical

a special symbol used in physics to describe the state of a particle.

For teachers: the row vector in Dirac notation, representing the complex conjugate of the corresponding ket vector.

- The professor explained how to multiply a bra and a ket in the equation.
- In quantum mechanics, the inner product of a bra and a ket results in a complex scalar value.

## Examples

- What's up, bra?
- He greeted his childhood friend with a quick 'Hey bra' before they started the game.
- The use of 'bra' as a vocative marker often signals a relaxed, fraternal social dynamic within specific subcultures, mirroring the function of 'dude' or 'mate' in other dialects.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.