We found 2 dictionaries that define the word an unknown quantity:

General (1 matching dictionary)

1. an unknown quantity: Dictionary.com

Miscellaneous (1 matching dictionary)

2. an unknown quantity: Idioms

▸ Words similar to an unknown quantity ▸ Usage examples for an unknown quantity ▸ Idioms related to an unknown quantity ▸ Wikipedia articles (New!) ▸ Words that often appear near an unknown quantity ▸ Rhymes of an unknown quantity ▸ Invented words related to an unknown quantity