unpaid
Not paid with money yet or not paid at all.
Unpaid describes work, bills, or obligations that haven't been paid for with money. An unpaid intern works at a company without receiving a paycheck, often to gain experience or learn new skills. An unpaid volunteer donates their time to help a cause they care about, like working at an animal shelter or coaching a youth sports team.
The word can also describe money someone owes but hasn't given yet. An unpaid bill is one that's due but the person hasn't sent the payment. If you borrow five dollars from a friend and forget to pay them back, that's an unpaid debt.
Sometimes unpaid work is a choice, like when people volunteer their time because they believe in something important. Other times it's unfair, like when workers complete a job but don't receive the wages they were promised. Understanding the difference matters: volunteering to help at your school's book fair is generous, but a business that refuses to pay its employees for their work is breaking the law.
The opposite of unpaid is paid, though we rarely need to say it since most jobs are assumed to come with payment unless specified otherwise.