Question

what is a refracted ray?

Answer 1

Refracted ray is the ray which do not reflect back and bends into the medium either towards the normal or away from it.

Answer 2

it is nothing but a ray which shows separation between two media by bending with respect to change in medium .e, when it passess from one media to another media. 
eg: mirages was formed due to these rays. this is due to the change in media (the density of air decreases as the rays travels from sky. so there will be a change in media. hence the ray suffers from refraction)