大だいの月つきだいのつきMeanings1expression, nounlong month; month with 31 daysRefers to a month that has 31 days. Often contrasted with 小の月 (short month, 30 days or less). Used in everyday contexts like calendars and scheduling.See also: 小の月1月がつは大だいの月つきです。January is a long month (has 31 days).
