be·​ta-block·​er ˈbā-tə-ˌblä-kər How to pronounce beta-blocker (audio)
: any of a class of drugs (such as propranolol) that decrease the rate and force of heart contractions and lower high blood pressure by blocking the activity of beta-receptors
beta-blocking adjective

Word History

First Known Use

1965, in the meaning defined above

Time Traveler
The first known use of beta-blocker was in 1965

Dictionary Entries Near beta-blocker

Cite this Entry

“Beta-blocker.” Dictionary, Merriam-Webster, Accessed 1 Apr. 2023.

Medical Definition


be·​ta-block·​er -ˈbläk-ər How to pronounce beta-blocker (audio)
: any of a group of drugs (as propranolol) that combine with and block the activity of a beta-receptor to decrease the heart rate and force of contractions and lower high blood pressure and that are used especially to treat hypertension, angina pectoris, and ventricular and supraventricular arrhythmias compare alpha-blocker

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