indenturedadjective
uk/ɪnˈdentʃəd/usrelating to an official agreement that someone will work for someone else for a length of time, especially in order to learn a job:
He served an indentured apprenticeship in mechanical engineering.
relating to an agreement in which someone works for someone else until they have paid back a debt, especially in the past when poor people worked for someone in another country in return for being taken to that country:
indentured labourers/servants/workers