light mill

English dictionary entry

Meanings

noun
  1. An airtight glass bulb containing a partial vacuum and a set of vanes, mounted on a spindle, which rotate when exposed to light, providing a quantitative measurement of electromagnetic radiation intensity.

Word forms

light mill light mills

Etymology

By analogy with windmill and water mill.

This entry uses open data from Wiktionary (CC BY-SA/GFDL). Word forms are used for search and are not indexed as separate pages.