What is meant by the term 'gravitational lens' ?

Answer 1

It is believed that gravity (if strong enough) can bend light rays. So it is possible that if you create or have at your disposal an intense gravitational field, you can use it to bend light rays and focus them on a distant object or use the gravitational field as a telescope to see further.

Answer 2

As per general theory of relativity space around large masses is curved. So rays which pass by the side of these large masses should also get bent this can be simulated optical lens which also bend rays of light & focus them to a point
Space around large masses curve the space & bend the light this curving of space is because of gravity it is called gravitation lens
This is phenomena which is confirmed by bending of light by sun gravity & many more example like Einstein’s cross etc

Answer 3

Gravity also pulls on light, just as it pulls us to the ground. If an object is massive enough, it's gravity will bend the light of things behind it like a lens, hence the name "gravitational lensing."

Answer 4

As the light passes around the outside diameter of a star or planet it is, thereafter, as it travels through space, lensed or projected in a Cone shape with the Small end at the receiving end where you stand and the base end being at the planet or star that it passed around/by.

That is why an eclipse can burn your eyes as the light is now concentrated.

Answer 5

above is correct, i'd just add that it is one of the methods now being used to detect extrasolar planets. the "lens" created by a high-mass star can amplify the image of a nearby planet.