Possible Definitions:
1. Semimonthly (a.) Coming or made twice in a month; as, semimonthly magazine; a semimonthly payment.
2. Semimonthly (n.) Something done or made every half month; esp., a semimonthly periodical.
3. Semimonthly (adv.) In a semimonthly manner; at intervals of half a month.