what is the term for the politicians that enforce party discipline in both the british and american legislatures, as well as many others?

The term you’re looking for is “whip” (or more specifically, party whip or chief whip).

Quick Scoop: What a whip does

In both the British and U.S. legislatures (and in many other parliamentary systems), a whip is the party official responsible for enforcing party discipline. They:

• Make sure members show up for key votes.

• Pressure or persuade members to vote with the party line.

• Act as go-betweens between party leadership and backbench or rank‑and‑file members.

In systems like the UK, the Chief Whip is the senior figure in charge of this operation. In the U.S. Congress, each party in each chamber has a Whip (e.g., House Majority Whip, Senate Minority Whip) who performs a similar role of vote counting and party discipline, even though formal discipline is usually looser than in strict Westminster-style systems.

So in short: those politicians who enforce party discipline in the British and American legislatures are called whips (often party whips or chief whips).

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