1 : the act of maintaining something or someone: such as
a : the act of keeping property or equipment in good condition by making repairs, correcting problems, etc.
The building has suffered from years of poor maintenance.
the costs of routine car maintenance
— often used before another noun
a maintenance worker [=a worker whose job is to keep property or equipment in good condition]
a maintenance fee
She works in the company's maintenance department.
b : the act of causing something to exist or continue without changing
maintenance of law and order
c: the act of providing support for someone or something
money for the family's maintenance