Hologram

Definition

Hologram is a noun referring to a three‑dimensional image formed by the interference of coherent light beams from a laser or other source; it can also denote the medium (photographic plate, film, or digital display) on which such an image is recorded or projected.

Parts of Speech

• Noun

Pronunciation

American English

• IPA: /ˈhɒl.ə.ɡræm/
• Respelling: HOL‑uh‑gram

British English

• IPA: /ˈhəʊ.lə.ɡræm/
• Respelling: HOH‑luh‑gram

Etymology

Mid 20th century: from holography + -gram ‘something written or recorded,’ from Greek hólos ‘whole’ + gráphō ‘to write.’

Derivatives

• holographic (adjective)
• holography (noun)
• hologrammatic (adjective, rare)

Synonyms

• 3D image
• laser image
• volumetric display

Antonyms

• two‑dimensional image
• flat image

Usage

The noun "hologram" is used in scientific, security, and entertainment contexts to refer to three‑dimensional projections or recordings. For example, "The museum displayed a hologram of a prehistoric creature," or "Many credit cards incorporate a hologram as a security feature."

Related Terms

• Holography: The technique of recording and reconstructing three‑dimensional images.
• Interference: The overlay of light waves that produces the holographic pattern.
• Laser: A coherent light source essential for producing clear holograms.
• Diffraction: The bending of light used to reconstruct the holographic image.
• 3D display: Any technology that presents images with depth perception.

Detailed Definitions

Noun

• A three‑dimensional image recorded on a light‑sensitive medium and reconstructed by coherent illumination – appears to float in space and can be viewed from different angles.
  • Example: "The art exhibit featured a hologram of an ancient artifact that appeared to float in midair."
• The physical medium (plate, film, or digital file) containing an interference pattern that produces a hologram – used in security, data storage, and display applications.
  • Example: "He examined the hologram on his credit card as proof of authenticity."