A paranormal characteristic of a person, who also may be a "psychic," who has psychic powers, but has not the ability to communicate with the dead. A sensitive is not a medium, nor is a medium necessarily a sensitive, rather an instrument for spirit communication.
Sensitives may possess profound psychometric, telepathic, clairvoyant (ordinary and medical) powers; and may also tell fortunes, find objects and render accurate character definitions. However, they may claim no external source.
This means, they have no spirit "guide" and there would not be any exteriorization of ectoplasm or psychic force to make manifestations from the Beyond possible.
Some mediums may also be sensitives, but possessing weak psychic powers, and they may subconsciously rely on these powers which cause them to give confused messages. The reason for this is that the subconscious mind may readily accept the suggestion of acting as a departed spirit.
The term "sensitive" became popular in the 19th century with the rise of Spiritualism, and use synonymously with "medium"; however, its main connotation is non-Spiritualist, approximating the term "psychic."