(Tıp, İlaç) 1. Atrial fibrillation (AF or A-fib) is the most common cardiac arrhythmia (abnormal heart rhythm) and involves the two upper chambers (atria) of the heart. Its name comes from the fibrillating (i.e., quivering) of the heart muscles of the atria, instead of a coordinated contraction.2. Very rapid uncoordinated contractions of the atria of the heart resulting in a lack of synchronism between heartbeat and pulse beat —called also auricular fibrillation
a trivial lie; "he told a fib about eating his spinach"; "how can I stop my child from telling stories?" tell a relatively insignificant lie; "Fibbing is not acceptable, even if you don't call it lying
If someone is fibbing, they are telling lies. He laughs loudly when I accuse him of fibbing. a small unimportant lie white lie (Perhaps from fable). fibbed fibbing to tell a small unimportant lie