[ tel-uh-skohp ]
See synonyms for: telescopetelescoped on

  1. an optical instrument for making distant objects appear larger and therefore nearer. One of the two principal forms (refracting telescope, or refractor ) consists essentially of an objective lens set into one end of a tube and an adjustable eyepiece or combination of lenses set into the other end of a tube that slides into the first and through which the enlarged object is viewed directly; the other form (reflecting telescope, or reflector ) has a concave mirror that gathers light from the object and focuses it into an adjustable eyepiece or combination of lenses through which the reflection of the object is enlarged and viewed.: Compare radio telescope.

  2. Telescope, Astronomy. the constellation Telescopium.

  1. consisting of parts that fit and slide one within another.

verb (used with object),tel·e·scoped, tel·e·scop·ing.
  1. to force together, one into another, or force into something else, in the manner of the sliding tubes of a jointed telescope.

  2. to shorten or condense; compress: to telescope the events of five hundred years into one history lecture.

verb (used without object),tel·e·scoped, tel·e·scop·ing.
  1. to slide together, or into something else, in the manner of the tubes of a jointed telescope.

  2. to be driven one into another, as railroad cars in a collision.

  1. to be or become shortened or condensed.

Origin of telescope

First recorded in 1610–20; tele-1 + -scope; replacing telescopium (from New Latin ) and telescopio (from Italian ); see -ium

Other words from telescope

  • non·tel·e·scop·ing, adjective

Words Nearby telescope Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use telescope in a sentence

British Dictionary definitions for telescope


/ (ˈtɛlɪˌskəʊp) /

  1. an optical instrument for making distant objects appear larger and brighter by use of a combination of lenses (refracting telescope) or lenses and curved mirrors (reflecting telescope): See also terrestrial telescope, astronomical telescope, Cassegrain telescope, Galilean telescope, Newtonian telescope

  2. any instrument, such as a radio telescope, for collecting, focusing, and detecting electromagnetic radiation from space

  1. to crush together or be crushed together, as in a collision: the front of the car was telescoped by the impact

  2. to fit together like a set of cylinders that slide into one another, thus allowing extension and shortening

  1. to make or become smaller or shorter: the novel was telescoped into a short play

Origin of telescope

C17: from Italian telescopio or New Latin telescopium, literally: far-seeing instrument; see tele-, -scope

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for telescope


[ tĕlĭ-skōp′ ]

  1. An arrangement of lenses, mirrors, or both that collects visible light, allowing direct observation or photographic recording of distant objects.♦ A refracting telescope uses lenses to focus light to produce a magnified image. Compound lenses are used to avoid distortions such as spherical and chromatic aberrations.♦ A reflecting telescope uses mirrors to view celestial objects at high levels of magnification. Most large optical telescopes are reflecting telescopes because very large mirrors, which are necessary to maximize the amount of light received by the telescope, are easier to build than very large lenses.

  2. Any of various devices, such as a radio telescope, used to detect and observe distant objects by collecting radiation other than visible light.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for telescope


A device used by astronomers to magnify images or collect more light from distant objects by gathering and concentrating radiation. The most familiar kind of telescope is the optical telescope, which collects radiation in the form of visible light. It may work by reflection, with a bowl-shaped mirror at its base, or by refraction, with a system of lenses. Other kinds of telescopes collect other kinds of radiation; there are radio telescopes (which collect radio waves), x-ray telescopes, and infrared telescopes. Radio and optical telescopes may be situated on the Earth, since the Earth's atmosphere allows light and radio waves through but absorbs radiation from several other regions of the electromagnetic spectrum. X-ray telescopes are placed in space.

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.