retain
US /rɪˈteɪn/
UK /rɪˈteɪn/

1.
2.
3.
4.
secure the services of (a lawyer, etc.) with a preliminary payment
:
•
The company decided to retain a new law firm.
•
He paid a fee to retain the services of a consultant.
secure the services of (a lawyer, etc.) with a preliminary payment