Words, terms, and phrases rarely/never used before 2020, but are now commonplace or were bandied about in this year:
Social Distancing
Shelter-in-place
P.P.E. (personal protective equipment)
The "worried well"
Feel free to add if you have any others. (Not long-standing words you happened to learned this year, but new/seldom-used terms that have come about this year and have been used frequently.)