Wiktionary
fibrillating
1 Splitting into fibrils or fibres. 2 Of a muscle, especially in the heart: undergoing fibrillation; quivering. v
(present participle of fibrillate English)
Usage examples of "fibrillating".
His mind was going and going, outracing the car, running on ahead of his thoughts, fibrillating like a bad heart until suddenly it stopped, dead still, conjectural operations ceased, and a clear bracing coldness descended through his overheated body in one long slow continuous wave.
My heart started fibrillating so I leaned back against the seat and started breathing in and out, slowly.