What is a Near-earth-asteroid?

Answer 1

Near-Earth Objects (NEOs) are comets and asteroids that have been nudged by the gravitational attraction of nearby planets into orbits that allow them to enter the Earth's neighborhood. Composed mostly of water ice with embedded dust particles

Answer 2

Following the standard definition of a NEO, somewhere between 14 and 15 thousand.

Answer 3

according to statistics maintained by NASA's Center for Near Earth Object Studies (CNEOS), 17,759 NEOs have been discovered: 107 near-Earth comets and 17,652 near-Earth asteroids.

Answer 4

It means:1) That it's an asteroid.

2) That somewhere in its orbit, it gets relatively close to Earth.