Real Dictionary

take over
phrasal verb: If someone takes over a country or building, they get control of it by force, for example with the help of the army.
phrasal verb: If you take over a company, you get control of it, for example by buying its shares.
phrasal verb: If you take over a job or role or if you take over, you become responsible for the job after someone else has stopped doing it.

take over in American English
to assume control or possession of
to assume management or possession of or responsibility for

take over in British English
to assume the control or management of
noun: the act of seizing or assuming power, control, etc