also: おとうづき · おととづき
noun
12th lunar month
Rare, archaic term for the 12th month of the lunar calendar, corresponding roughly to January in the Gregorian calendar. Cross-referenced with 師走 (しわす), the more common name for the same month.
See also: 師走
古い暦では、弟月は年の最後の月を指す。
In old calendars, 弟月 refers to the last month of the year.
弟月は師走と同じ月を表すが、あまり使われない。
弟月 represents the same month as 師走, but it is rarely used.
師走 is the standard, widely recognized term for the 12th lunar month, while 弟月 is a rare synonym.
The exact derivation is uncertain; the kanji 弟 (younger brother) and 月 (month) may reflect an old naming convention for the last month of the year, but this is not well-documented.