The ancient Greeks and Romans knew that there were times when you didn’t want to be recognized. For example, a myth tells how Zeus and Hermes visited a village incognito and asked for lodging. The apparently penniless travelers were turned away from every household except that of a poor elderly couple named Baucis and Philemon, who provided a room and a feast despite their own poverty. The Romans had a word that described someone or something unknown (like the gods in the tale): incognitus, a term that is the ancestor of our modern incognito. Cognitius is the past participle of the Latin verb cognoscere, which means “to know” and which also gives us recognize, among other words.
COUP DE GRACE
A decisive finishing blow blow, act, or event. Borrowed directly from French and first appearing in English at the end of the 17th century, coup de grâce translates literally as “stroke of grace” or “blow of mercy,” and originally referred to a mercy killing, or to the act of putting to death a person or animal who was severely injured and unlikely to recover. (In some contexts the term is used to refer to the final act of executing a convicted criminal.) Later, coup de grâce had come to mean “an act or event that puts a definite end to something.” Other coup terms that have made the jump from French to English include coup de main, for a sudden, forceful attack, and coup d’état for a violent overthrow of a government usually by a small group.
Acquiesce means essentially “to comply quietly,” so it should not surprise you to learn that it is ultimately derived from the Latin verb quiēscere, meaning “to be quiet.” It arrived in English in the early 1600s, via the French acquiescer, with the senses “to agree or comply” and “to rest satisfied” (this latter sense is now obsolete). An early example of the word acquiesce in the sense of “to agree or comply” can be found in the writings of the English philosopher Thomas Hobbes who, in his 1651 masterpiece, Leviathan, argued that people must subject themselves completely to a sovereign and should obey the teachings of the church. Encouraging his readers to adopt his position he wrote, “Our Beleefe … is in the Church; whose word we take, and acquiesce therein.” – Source – Merriam-Webster