Theta plane and phi plane in 3-D Antenna measurement

For antenna 3-D measurement, what is the definition of Theta plane and phi plane ?

Theta plane is just used for the case of phi = 0 degree ?

The phi plane is just used for the case of theta = 90 degree ?


How about other case for example theta = 50, phi form 0 to 360? or phi = 50, theta form 0 to 180?

Is there some term for these planes?

Many thanks for you helps