ground truth
n.— «Weather spotters provide what’s called “ground truth” to the National Weather Service and emergency weather management. “We’re needed because cloud-piercing Doppler radar is very good at helping the National Weather Service see what’s going on in the upper atmosphere, but it’s unable to detect what’s actually happening on the ground because of the curvature of the Earth.”» —“Volunteers track storms” by Debra Carr-Elsing Capital Times (Madison, Wisconsin) Oct. 26, 2006. (source: Double-Tongued Dictionary)
Further reading
Amid a 1796 heat wave, Jane Austen wrote to her sister, “What dreadful hot weather we have! It keeps me in a continual state of inelegance.” This is part of a complete episode. Transcript of “Jane Austen’s Continual State of Inelegance in a 1796...
If you’re ever near a sundial, step closer and look for a message. Many sundials bear haunting, poetic inscriptions about the brevity of life. Plus, language development in toddlers: why and how little ones pick up the exclamation Uh-oh! And a new...