mask up

Popularized in 2020 during the COVID-19 pandemic.

mask up (third-person singular simple present masks up, present participle masking up, simple past and past participle masked up)

1. (intransitive) To put on a mask, especially a safety mask or a medical facemask.
   • 2001, Eric R. Taylor, Lethal Mists: An Introduction to the Natural and Military Sciences of Chemical, Biological Warfare and Terrorism, Huntington, NY: Nova Science Publishers, →ISBN, page 181:

     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 that the foot soldier has against airborne chemical agent attack.

   • 2021, Rachel Clarke, Breathtaking: Inside the NHS in a Time of Pandemic, London: Little, Brown, →ISBN, page unknown:

     Winston arrived twenty-four hours ago. Before I can enter the ward where he lies, I need to mask up. In theory, the masks we all wear – paper thin, though reinforced with a water-resistant coating – will prevent the virus from contaminating our mouth or nose, even when a patient coughs in our direction.