cachinnate
Concise Oxford English Dictionary © 2008 Oxford University Press:
cachinnate /ˈkakɪneɪt/
▶verb literary laugh loudly.
– derivatives
cachinnation noun.
cachinnation noun.
– origin C19 (earlier (C17) as cachinnation): from L. cachinnat-, cachinnare ‘laugh loudly’.
'cachinnate' also found in these Oxford entries:

