variants or less commonly AFib or Afib

Word History


by shortening

First Known Use

1988, in the meaning defined above

Time Traveler
The first known use of A-fib was in 1988

Dictionary Entries Near A-fib

Cite this Entry

“A-fib.” Dictionary, Merriam-Webster, Accessed 10 Dec. 2023.

Medical Definition


variants also AFib or Afib
: atrial fibrillation
A-fib occurs when the top chambers of the heart, responsible for bringing blood back from the rest of the body, start to flutter.Forbes
Individuals who walked two to three miles per hour … had a 32 percent lower risk of developing AFib, whereas those who walked more than three miles per hour (moderate pace) lowered their risk by 41 percent.Food & Fitness Advisor
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