Ectoplasm is a term coined by Charles Richet to denote a substance or spiritual energy "exteriorized" by physical mediums

Mediumship

Mediumship is described as a form of communication with spirits. It is a practice in religious beliefs such as Spiritualism, Spiritism, Espiritismo, Candomblé, Voodoo and Umbanda.- Concept :...

. Ectoplasm is said to be associated with the formation of spirit

Spirit

The English word spirit has many differing meanings and connotations, most of them relating to a non-corporeal substance contrasted with the material body.The spirit of a living thing usually refers to or explains its consciousness.The notions of a person's "spirit" and "soul" often also overlap,...

s, and asserted to be an enabling factor in psychokinesis

Psychokinesis

The term psychokinesis , also referred to as telekinesis with respect to strictly describing movement of matter, sometimes abbreviated PK and TK respectively, is a term...

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Ectoplasm is said to be produced by physical mediums when in a trance state. This material is excreted as a gauze-like substance from orifices on the medium's body and spiritual entities are said to drape this substance over their nonphysical body, enabling them to interact in our physical universe.

Although the term is widespread in popular culture, the physical existence of ectoplasm is not accepted by science.