# tou

CEFR C2 · Noun

Source: https://englishreference.com/word/tou
Updated: 2026-05-19

## Definition

a very small amount of something. You use this word when you want to say there is almost nothing left of a substance.

For teachers: a minute quantity or trace of a substance. Often used in scientific or technical contexts to describe residual amounts.

## Examples

- Only a tiny tou of the chemical remains.
- The lab technician noted that only a tou of the original sample was sufficient for the test.
- Even a tou of the catalyst can significantly accelerate the reaction, making it a highly efficient choice for industrial processes where material conservation is critical.

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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.