1) Employment 2) One way to earn 3) Work 
• (n.) Work done by the piece or job; work paid for at a rate based on the amount of work done, rather than on the time employed.
Work in which payment is based on the amount of work done regardless of the time it takes to do it
A remuneration system where the wage level is directly related to output levels.
Piece'work` noun Work done by the piece or job; work paid for at a rate based on the amount of work done, rather than on the time employed. « The reaping was piecework , at so much per acre.» R. Jefferies. 
[n] - work paid for according to the quantity produced
noun work paid for according to the quantity produced