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coronograph

[kuh-roh-nuh-graf, -grahf]

noun Astronomy.

coronagraph.

Origin of coronograph

First recorded in 1880–85
Related formsco·ro·no·graph·ic [kuh-roh-nuh-graf-ik] /kəˌroʊ nəˈgræf ɪk/, adjective

coronagraph

or co·ro·no·graph

[kuh-roh-nuh-graf, -grahf]

noun Astronomy.

an instrument for observing and photographing the sun's corona, consisting of a telescope fitted with lenses, filters, and diaphragms that simulate an eclipse.

Origin of coronagraph

1885–90; earlier coronograph. See corona, -graph
Related formsco·ro·na·graph·ic [kuh-roh-nuh-graf-ik] /kəˌroʊ nəˈgræf ɪk/, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for coronograph

coronagraph

coronograph

noun

an optical instrument used to simulate an eclipse of the sun so that the faint solar corona can be studied
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