Semimonthly

Webster's Dictionary of the English Language

·adv In a semimonthly manner; at intervals of half a month.

II. Semimonthly ·noun Something done or made every half month; ·esp., a semimonthly periodical.

III. Semimonthly ·adj Coming or made twice in a month; as, semimonthly magazine; a semimonthly payment.