# unknown quantity

idiom

Source: https://englishreference.com/idiom/unknown-quantity
Updated: 2026-08-10

## Meaning

A person or thing whose nature or value is a mystery.

## Examples

- The new player is an unknown quantity for our team.
- We have no data on this candidate, so they remain an unknown quantity before the final interview.
- Because the startup had never launched a product before, investors viewed the company as an unknown quantity in a competitive market.

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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.