periodic motion is a motion of body wich repeats itself in equal intervals of time , but a oscillatory motion is a periodic motion which is about a mean position . so all periodic motions could not be a oscillatory motion , but all oscillatory motions are periodic in nature.

Oscillatory motion is also called vibratory motion while periodic motion is a motion which is repeat itself after a specific interval. Periodic motion may be rotatory or vibratory.

if a motion repeats it self after equal intervals of time it is called a periodic motion, if u understand this definition u will know that a fan is undergoing the periodic motion as if of its blades in proper words the blades of an electric fan is a periodic motion

there are 5 kinds of motion. they are 1.translatory motion 2.rotatory motion 3.transla- rotatory motion 4.periodic motion 5.vibratory motion

Both. Periodic motion refers to any motion that repeats itself periodically. The oscillatory motion exhibited by swinging of arms is one type of periodic motion. Orbital motion of a planet is another type of periodic motion. The motion of a spring is another type, etc.