umbra versa

== English == === Etymology === First attested in Modern English in 1688, although the phrase was also used in Middle English by Geoffrey Chaucer (c. 1343–1400) in his Treatise on the Astrolabe; Latin: umbra (“shadow”) + versa (feminine nominative singular of versus, “turned”) = “turned shadow”; compare umbra recta. === Pronunciation === (Received Pronunciation) enPR: ŭmʹbrə vûrʹsə, IPA(key): /ˈʌmbɹə ˈvɜːsə/ === Noun === umbra versa On a shadow in the shape of a right triangle, the length of the shadow's edge opposite to a measured angle. ==== Synonyms ==== umbra stans