apparition

As a noun apparition

is an act of becoming visible; appearance; visibility.

As an adjective undefined is

lacking a definition or value.

As nouns the difference between simulacrum and apparition

is that simulacrum is an image or representation while apparition is an act of becoming visible; appearance; visibility.

As nouns the difference between doppelganger and apparition

is that doppelganger is doppelganger, while apparition is an act of becoming visible; appearance; visibility.

As nouns the difference between apparition and visual

is that apparition is an act of becoming visible; appearance; visibility while visual is any element of something that depends on sight.

As an adjective visual is

related to or affecting the vision.

As nouns the difference between poltergeist and apparition

is that poltergeist is an unseen ghost which makes noises and causes disruption, especially by causing physical objects to move or fly about while apparition is an act of becoming visible; appearance; visibility.

As a verb appear

is (label) to come or be in sight; to be in view; to become visible.

As a noun apparition is

an act of becoming visible; appearance; visibility.

As nouns the difference between apparition and body

is that apparition is an act of becoming visible; appearance; visibility while body is physical frame.

As a verb body is

to give body or shape to something.

As nouns the difference between manifestation and apparition

is that manifestation is the act or process of becoming manifest while apparition is an act of becoming visible; appearance; visibility.

Presence is a synonym of apparition.

As nouns the difference between presence and apparition

is that presence is presence while apparition is an act of becoming visible; appearance; visibility.

As nouns the difference between illusion and apparition

is that illusion is anything that seems to be something that it is not while apparition is an act of becoming visible; appearance; visibility.