nosism (NO-siz-em) noun
The use of ‘we’ in referring to oneself.
[From Latin nos (we).]
As it’s often used by editors, it’s also known as the “editorial we”.
It’s also called “the royal we” owing to its frequent use by royalty.
Mark Twain once said, “Only kings, presidents, editors, and people
with tapeworms have the right to use the editorial ‘we’.”
-Anu Garg (words at wordsmith.org)