# Molly

/ˈmɑɫi/ (US) · /mˈɒli/ (UK)

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

## Senses

### 1. a name

noun · CEFR A1

a common nickname for the names Mary or Margaret.

For teachers: a diminutive form of the female given names Mary or Margaret.

- My aunt's name is Mary, but everyone in the family calls her Molly.
- While her legal documents state Margaret, she has gone by Molly since her early childhood in Dublin.

### 2. a fish

noun · CEFR B2

a small, colourful tropical fish often kept in home aquariums.

For teachers: any of several small, live-bearing tropical fish of the genus Poecilia, popular in the aquarium trade.

- He added two black mollies to his fish tank yesterday.
- The common molly is highly prized by amateur aquarists for its hardiness and variety of colour morphs.

### 3. a drug

noun · CEFR C2 · Slang

a slang name for the drug MDMA, usually in powder or crystal form.

For teachers: a slang term for the drug MDMA, specifically referring to the substance in a powdered or crystalline state rather than pill form.

- The police warned the public about the dangers of taking molly at music festivals.
- The rise of molly in the club scene has been attributed to its reputation for being a purer form of ecstasy.

Usage: Uncountable in this sense.

## Examples

- He was arrested for possession of Molly.
- Public health officials issued a warning after several people were hospitalized for taking Molly that had been mixed with dangerous synthetic chemicals.
- The rise of Molly in popular culture has led to a dangerous misconception among young adults that the powdered form of the drug is inherently safer or purer than its pill-based counterparts.

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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.