Reference meaning
heliograph
Last updated
an apparatus for sending telegraphic messages by using a mirror to turn the sun's rays off and on
Other meanings
2. verb
signal by means of a mirror and the using the sun's rays
Source and scope
This definition is reproduced from Princeton WordNet 3.0, sense 03512452-n, under the WordNet 3.0 License. It has not yet received VocabularyBase editorial review. Read the source and license details.