Webster Dictionary(0.00 / 0 votes)Rate this definition: 1  Hypo-. a prefix signifying a less quantity, or a low state or degree, of that denoted by the word with which it is joined, or position under or beneath. 2  Hypo-.
Confidence votes 25. St Patrick's Cathedral in New York City. ***Actually, the Basilica of the National Shrine of the Immaculate Conception in DC is larger than St. Patrick's in NYC. The National Shrine is the largest Roman Catholic church in the U.S., and one of the 10 largest Roman Catholic churches in the world.
The Catholic Church, also known as the Roman Catholic Church, is the largest Christian church, with more than 1.25 billion members worldwide.One of the oldest religious institutions in the world, it has played a prominent role in the history of Western civilisation.he Catholic Church, also known as the Roman Catholic Church, is the largest Christian church, with more than 1.25 billion members worldwide.