大だいの月つき

expression, noun

long month; month with 31 days

Refers 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).

• 大だいの月つきと小しょうの月つきを覚おぼえる歌うたがある。

  There is a song to remember the long months and short months.