1.  A person, most frequently a woman, who communicates with spirits, usually on behalf of another person. There are several overlapping types of mediumship:
Spirit Medium: communicates with spirits
Trance Medium: goes into a trance to communicate with spirits
Mental Medium: answers question given by “sitters” at a séance
Physical Medium: less common that 100 years ago, this is the type of medium who produces paranormal activity during a séance.

2.  A person who is sensitive to the vibrations from the spirit world. They are able to communicate with those on the spirit side of life through various means, delivering information and assistance to those who ask. All mediums are also psychics.