a telescope for viewing the sun, adapted to protect the eye of the viewer from the sun's glare
Derived forms
helioscopic (ˌhiliəˈskɑpɪk)
adjective
helioscopy (ˌhiliˈɑskəpi)
noun
Word origin
[1665–75; helio- + -scope]This word is first recorded in the period 1665–75. Other words that entered Englishat around the same time include: newsletter, regulation, suite, wader, wig-scope is a combining form meaning “instrument for viewing,” used in the formation of compoundwords. Other words that use the affix -scope include: electroscope, fiberscope, laryngoscope, stereoscope, stroboscope