noun
one's future; what lies ahead
Refers to the future course of one's life, often with a sense of uncertainty or concern. Commonly used in expressions like おいさき短い (one's remaining life is short) or おいさき真っ暗 (the future looks dark).
こんなに若くして病気になるなんて、おいさきが思いやられる。
Getting sick at such a young age, I worry about what the future holds.
生い先の長い若者に重労働は避けさせたい。
I want young people with long futures ahead to avoid such heavy labor.
Compound of 生い (oi, 'growing up; living', from verb 生いる) and 先 (saki, 'ahead; future'). The exact historical derivation is uncertain, but the word has been used since at least the Edo period to refer to one's remaining years or future prospects.