1. Relating to an igneous rock in which the crystals are so coarse that individual minerals can be distinguished with the naked eye.

Phaneritic rocks are intrusive rocks that cooled slowly enough to allow significant crystal growth.

2. A references to igneous rock grain size.

It means that the size of the grains in the rock are large enough to be distinguished with the unaided eye as opposed to aphanitic; which is too small to be seen with the naked eye.