Laghukoshasamgraha 12.8

12.8

ānakaḥ paṭahe bheryā nadanmedhamṛdaṅgayoḥ |
ātaṅko ruji śaṅkāyāṃ santāpe murajadhvanau ||

ānaka is used for a small drum, a kettle-drum, a thundering cloud, and a mṛdaṅga drum;
ātaṅka is used for illness, fear, anguish, and the sound of a muraja drum;