"defined plan" is correct and can be used in written English.
It refers to a specific and clearly outlined course of action or strategy. Example: "The company has a well-defined plan for expanding into international markets."
In addition, these investors have a defined plan to sell their investments after a specific amount of time.
Mr. Pickens does not have a defined plan for this venture, but when he sees another property where the price or location is right, he'll jump in.
The vaguely defined plan for the Arts and Industries Building, a structure that remains mostly dormant despite a $55 million renovation, was another point of contention.
It is done within a carefully defined plan and with meaningful participation of employees, outside of what is normally thought of as traditional maintenance.
His whole approach to the game was non-systematic: he was spontaneous, not disciplined, and got by on the strength of his individual skill and virtuosity, rather than playing for the collective according to a rigorously defined plan.
But Washington is where he will continue his career in 2019, and he'll do so in a catching tandem that has a lot of potential and, at the moment, no defined plan.
Wooden believed that you had to follow a defined, planned out, routine that maximized efficiency.
They also define plans, programs, and activities they believe are essential for their division's performance.
These models may help defining plans for improvement that require less effort from the DMUs.
NASA is currently in the process of defining plans for a new hypersonic technology program.
It offers framework to define plans which aim at preventing, rather than striving to cure malaria.
