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fibrillation vs. fasciculation

[fib-ruh-ley-shuhn, fahy-bruh-] / ˌfɪb rəˈleɪ ʃən, ˌfaɪ brə- /

noun

  1. the formation of fibrils, or fine fibers or filaments.

  2. Pathology. uncontrolled twitching or quivering of muscle fibers, such as those of the heart.

[fuh-sik-yuh-ley-shuhn] / fəˌsɪk yəˈleɪ ʃən /

noun

  1. a fascicular condition.