X factor

American  

[eks fak-ter] / ˈɛks ˌfæk tər /

noun

plural

X factors

1. an essential quality or feature that is difficult to identify or express.

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Example Sentences

"He is the X factor of my team. He has been amazing, scoring in every game. Tonight he sent a message to the rest of the side with the way he ran and fought."

From Barron's • Jan. 9, 2026

Over the last three games, Knecht has emerged as an X factor for the Lakers, the type of rookie weapon teams don’t normally draft midway through the first round.

From Los Angeles Times • Nov. 17, 2024

Payne was a global star and part of the much-loved boyband, which was created on The X factor TV show in 2010.

From BBC • Oct. 18, 2024

Add it all up to the biggest X factor of the final stretch.

From New York Times • Jan. 14, 2024

To turn the key in the lock, to open the door, he must change the physical reality to balance the equation, rather than supply the X factor to keep reality unchanged.

From Eight Keys to Eden by Clifton, Mark