サイ, セイ, とし, とせ, よわい
year-end, age, occasion, opportunity
JLPT3 G7 S13 F269
As per 戉# (scoop out) + a modified form of 歩 walk → walk about a field, harvesting rice by scooping it from the ears of the plant with a sickle-like implement → *year*; *age* (← harvest as the end of a long agricultural cycle; compare 年).
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