Duodisimally

duodecimal = base-12 number system

examples include the clock, the zodiac, the calendar's months, the foot's inches, the words "dozen" and "gross" (a dozen dozens), etc. -- a common number system in ancient societies due to its divisibility by 2, 3, 4, and 6.

may also be a pun on "Dewey Decimal" system, the method devised in 1870 (and no longer preferred by so many libraries) of arranging all possible books in a library.

also suggests "dismal," whose etymology echoes the (12-month) calendar and (12-sign) zodiac theme: "dismal" = "mal dies" = "evil days," two days of each month determined to be bad by methods supposedly deriving from ancient Egyptian astrology; this meaning held sway for hundreds of years before the word acquired its modern sense