Mechanical waves require a medium to travel through. Examples of mechanical waves are sound waves, water waves, a vibrating string. (See related link). Electromagnetic waves â¦(such as light, radio waves, X-rays, microwaves) do not need a medium to travel through, so these are not mechanical waves.
Photostat definition, a camera for making facsimile copies of documents, drawings, etc., in the form of paper negatives on which the positions of lines, objects, etc., in the originals are maintained. a copy made with this camera.
Wiktionary(3.00 / 1 vote)Rate this definition: 1  photograph(Noun) A picture created by projecting an image onto a photosensitive surface such as a chemically treated plate or film, CCD receptor, etc. 2  photograph(Verb) To take a photograph of. 3  photograph(Verb) To take photographs. 4  photograph(Verb) To appear in a photograph.