# billy

/ˈbɪɫi/ (US) · /bˈɪli/ (UK) · CEFR C2 · Noun

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

## Definition

a slang name for the drug amphetamine. People use this word in very casual or street settings.

For teachers: a slang term for amphetamine, typically used in the United Kingdom and Australia. Highly informal in register and restricted to colloquial or drug-related contexts.

## Examples

- He was arrested for carrying a small bag of billy.
- The police found several grams of billy hidden in the back of the suspect's vehicle during the search.
- While the term is widely recognised in certain subcultures, using billy in a formal setting would be entirely inappropriate due to its strong association with illegal substance use.

## Usage notes

- Uncountable when referring to the substance; primarily British and Australian slang.

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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.