Bicameral
Glossary·Verified 2026-07-10
Definition
A bicameral legislature has two separate chambers, typically a house of representatives (or assembly) and a senate, that must both pass identical bill text before it can go to the governor or president for signature. The alternative is a unicameral legislature, a single chamber.
Why it matters
Bicameralism doubles the number of committees, floor votes, and choke points a bill must survive, part of why so few introduced bills ever become law. A bill can pass one chamber easily and still die quietly in the other without ever getting a floor vote there.
Seen in the wild
Every U.S. state legislature is bicameral except Nebraska's, which has operated as a single, nonpartisan chamber since voters restructured it through a 1934 constitutional amendment.1