trimonthly

[ trahy-muhnth-lee ]
/ traɪˈmʌnθ li /

adjective

occurring, taking place, done, or acted upon every three months.

Origin of trimonthly

First recorded in 1855–60; tri- + monthly

British Dictionary definitions for trimonthly

trimonthly
/ (traɪˈmʌnθlɪ) /

adjective, adverb

every three months