nibs definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
Informal an important, or esp. self-important, person: preceded by his or, occas., her
Origin: ; from uncertain or unknown; perhaps
nibs definition by American Heritage Dictionary
A person in authority, especially one who is self-important. Used with his or her: His nibs says we must do it.
Origin: Perhaps alteration of nob2.