cachinnation (n.)

"loud laughter," 1620s, from Latin cachinnationem (nominative cachinnatio) "violent laughter, excessive laughter," noun of action from past-participle stem of cachinnare "to laugh immoderately or loudly," of imitative origin. Compare Sanskrit kakhati "laughs," Greek kakhazein "to laugh loudly," Old High German kachazzen, English cackle, Armenian xaxanc'.