Question

why aeroplane window in oval shape​

Answer 1

because it has no use in Air. makers do not want to waste their money in making large window

Answer 2

Answer:

By curving the window, the stress that would eventually crack the window corner is distributed and the likelihood of it breaking is reduced. Circular shapes are also stronger and resist deformation, and can thus survive the extreme differences in pressure between the inside and outside of the aircraft.