noun, noun or participle which takes 'suru'
making some money; earning a bit of cash
Often implies a one-time or supplementary effort to earn money, not a regular job. Used as a noun or with する to mean 'to make some money'.
週末にアルバイトで一稼ぎしよう。
Let's make some money with a part-time job this weekend.
彼は株で一稼ぎしたらしい。
It seems he made some money in stocks.
稼ぎ is a general term for earnings or work to earn money, while 一稼ぎ emphasizes a single, often opportunistic, money-making effort.
Compound of 一 (ひと, 'one') and 稼ぎ (かせぎ, 'earning'), literally 'one earning'.