The 5 most prestigious universities in the United States:

Harvard University
Yale University
Princeton University
Stanford University
Massachusetts Institute of Technology
Admissions to HYPSM is extremely competitive.
by dedicated scholar November 16, 2011
Harvard, Yale, Princeton, Stanford, MIT
i.e. Prestigious American universities.
I know this really smart guy. He got into HYPSM
by PedroFile April 13, 2009
This stands for Harvard, Yale, Princeton, Stanford, MIT.
There are plenty of Asians at HYPSM and their peer institutions.
by 1XxXLuther BlissettXxX1 April 28, 2009
Top schools used by Americans in the US: Harvard, Yale, Princeton, Stanford, and MIT.

However, schools like Berkeley and Caltech are equal to or more well-known than Princeton in terms of prestige and clout internationally and arguably domestically.
Princeton kids say, “yeah, I go to HYPSM,” or “oh, I go to the number 1 school on USNews,” but never say that “they go to Princeton” when abroad directly to college bound folks because HYPSM is more well known and not accurate.