noun
Archaic poetic name for the eighth month of the lunar calendar, literally 'month when swallows leave'. Used in classical literature and poetry; not used in modern everyday language.
See also: 葉月
「燕去り月」は、旧暦八月の雅称の一つである。
'Tsubamesarizuki' is one of the elegant names for the eighth month of the old lunar calendar.
葉月 is the more common classical name for the eighth lunar month, while 燕去り月 is a rarer, more poetic alternative.
From 燕 (tsubame, 'swallow') + 去り (sari, 'leaving') + 月 (tsuki, 'month'), referring to the time when swallows migrate south in autumn. The exact historical origin is uncertain.