bimonthlyPronunciation: /bʌɪˈmʌnθli/Definition of bimonthly adjective occurring or produced twice a month or every two months:a bimonthly newsletter adverb twice a month or every two months: the magazine appears bimonthly noun (plural bimonthlies) a periodical produced twice a month or every two months. bimonthly in other Oxford dictionaries Definition of bimonthly in the US English dictionary