Answer: HALLELUJAH
Explanation: The 11-asterisked entries each have the first three letters of the month backward within them (i.e. INAJAM contains JAN, BEFAIR contains FEB, and so forth). Month abbreviations are hinted by MOS, and the backwardness of time-related entries is alluded to by the title. The one month whose abbreviation is missing is July's (fitting, as we're in that now, of course!). Its three-letter abbreviation is JUL, which when backward is LUJ. Perhaps the only common word at all, and therefore the only ten-letter word (I researched this!!), with the trigram LUJ is HALLELUJAH, the answer to the meta and a very fitting exclamation when you solve one!