zeitgeber
n.— «Light and temperature are the only periodic or quasi-periodic environmental variables to which endogenous oscillation can be coupled: in nature they entrain the endogenous oscillation, thereby controlling period and establishing appropriate phase. They are, to use Aschoff’s phrase, the principal Zeitgeber.» —“On the Significance of Transients in Daily Rhythms” by Colin Pittendrigh, Victor Bruce, Peter Kaus Proceedings of the Natl. Acad. of Sciences (US) Sept. 15, 1958. (source: Double-Tongued Dictionary)
Further reading
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...
Kelly from Butte, Montana, recalls that when a few morsels remained at the end of a meal, her grandmother would say, Make it a nice day tomorrow, meaning everyone should eat all their food. A version used by a childhood friend’s family was Make it a...