Reference meaning
X factor
Last updated
An unknown or hard-to-define influence; a factor with unknown or unforeseeable consequences.
Other meanings
2. noun
A special talent, ability or quality or its indefinable cause.
3. noun
Prothrombinase.
4. noun
The proportionality constant which converts CO emission line brightness to molecular hydrogen mass.
Source and scope
This definition is reproduced from English Wiktionary, sense en-X_factor-en-noun-F1fO4ust, under the CC BY-SA 4.0. It has not yet received VocabularyBase editorial review. Read the source and license details.