Definition of Dobsonian in English:



  • Relating to or denoting a low-cost Newtonian reflecting telescope with large aperture and short focal length, or the simple altazimuth mount used for it.

    • ‘I was manning the smaller of the two telescopes that comprise the LCT, a 12.5' f/4.8 Newtonian reflector on a Dobsonian mount.’
    • ‘My existing telescope is one of these, a 13.1' f/4.5 Newtonian reflector on a Dobsonian mount.’
    • ‘With Dobsonian telescopes and CCD sensors, the Earth acquired hundreds of thousands of new eyes, probing space and recording events that would have gone unnoticed by the few thousand professionals.’


1980s from the name of John Dobson, American amateur astronomer, + -ian.