# marbles

/ˈmɑɹbəɫz/ (US) · /mˈɑːbəlz/ (UK) · CEFR B1 · Noun

Source: https://englishreference.com/word/marbles
Updated: 2026-05-07

## Definition

small, round balls made of glass or stone that children use to play games. In a casual way, it can also mean someone's ability to think clearly or stay sane.

For teachers: small, spherical toys typically made of glass, clay, or stone, used in various traditional games. In idiomatic usage, refers to one's mental faculties or sanity.

## Examples

- The children are playing with colorful glass marbles in the park.
- After working sixteen hours a day for a month, he felt like he was losing his marbles.
- While the physical game of marbles has declined in popularity, the idiomatic expression regarding one's cognitive stability remains a staple of colloquial English.

## Pitfalls

- Not "He lost his marble." but "He lost his marbles." — The idiom for losing one's sanity always uses the plural form 'marbles'.

## Usage notes

- When referring to the game or the objects, it is a plural countable noun; in the idiomatic sense 'lose one's marbles', it is always plural.

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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.