Technically there isn't one.
The closest segment of US government to resemble parliament is Congress.
Prime Minister
There is no US "parliament". Parliament is the legislative body in Great Britain and in some other countries as well, but not in the United States. In the United States the legislative body is called Congress. The function of Congress is primarily to make laws governing the nation.
mocking a parliament is called mock parliament
Owls are solitary . . . if they do get together, flying or otherwise, the group is called a "Parliament".
Parliament of India is called as Sansad Bhawan
In the US this is known as Congress. In Australia, they make up the Federal Parliament.
It is called Parliament House.
A group of owls is called a parliament. A group of their young would be a clutch.
An MP or "member of parliament".
Instead of flocks it is called parliament of rooks
The tower in the center of the Canadian parliament buildings is called the Peace Tower.
The lower house of Parliament in India is called the Lok Sabha.