mask up

In real, traceable use. Part of the curated seed collection; community review is coming.

Meaning · English

To put on a mask, especially a safety mask or a medical facemask.

Where it’s used: Used American English

Examples

Soldiers are trained to immediately mask up at the first sign or suspicion that a chemical attack is in progress and then immediately give the signals themselves. In conjunction with any early warning of chemical attack, the donning of the protective mask will provide the best possible protection th

Usage example from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30)

Sources & notes

Adapted from English Wiktionary (CC BY-SA 4.0, retrieved 2026-07-30 via kaikki.org).

Common questions

What does “mask up” mean?

To put on a mask, especially a safety mask or a medical facemask.

Is “mask up” formal or informal?

No register label has been reviewed yet — treat it as neutral and check the usage notes above.