From Greek: πτερόν (pteron) = wing (because it was first found in butterfly wings).
pterin (countable and uncountable, plural pterins)
(organic compound) A ketonic amide derivative of pteridine responsible for some of the colouring in nature. It is also a component of folic acid.
• Petrin, Pinter, Pitner, e-print, nipter, pinter, pre-tin, pretin, reptin, terpin
Source: Wiktionary
27 May 2025
(noun) the property of being directional or maintaining a direction; “the directionality of written English is from left to right”
The Boston Tea Party helped popularize coffee in America. The hefty tea tax imposed on the colonies in 1773 resulted in America switching from tea to coffee. In the lead up to the Revolutionary War, it became patriotic to sip java instead of tea. The Civil War made the drink more pervasive. Coffee helped energize tired troops, and drinking it became an expression of freedom.
