Continuing my investigation of foreign phrases commonly used in English:
Ad hoc: Created or done for a particular purpose as necessary, made or happening only for a particular purpose or need, not planned before it happens. The phrase is Latin and means “to this.”
Ad nauseum: To a sickening degree, referring to something that has been done or repeated so often that it has become annoying, continued to the point of nausea. Once again from Latin, the phrase means “to sickening.”
Sang-froid: Cold blood in French. When used in English, it means composure, self-possession, calmness, coolness of mind, the ability to remain calm in a dangerous or difficult situation.
Caveat emptor: A Latin phrase that literally means “let the buyer beware.” According to Wikipedia, the phrase is a short form of Caveat emptor, quia ignorare non debuit quod jus alienum emit (Let a purchaser beware, for he ought not to be ignorant of the nature of the property which he is buying from another party.) In other words, the buyer should assure himself that the product is good and that the seller had the right to sell it, as opposed to receiving stolen property.
Persona non grata: Latin for “an unwelcome person.” The term in a diplomatic sense refers to a foreign person whose entering or remaining in a certain country is prohibited by that country.
Laissez faire: French for “let people do as they choose.” The phrase was a motto of eighteenth century French economists who protested excessive government regulation of industry. The actual translation of the words is “let do.” The implication is the less the government is involved in the economy, the better off business will be, and by extension, society as a whole.
Deus ex machina: Literally, “God out of the machine” in Latin. Wikipedia says it is a Latin calque from Greek ἀπὸ μηχανῆς θεός (apò mēkhanês theós) “god from the machine.” The term was coined from the conventions of ancient Greek theater, where actors who were playing gods were brought onto stage using a machine. The machine could be either a crane (mechane) used to lower actors from above or a riser that brought them up through a trapdoor. In modern speech, it means a plot device in fiction or theater whereby a seemingly unsolvable problem in a story is suddenly and abruptly resolved by an unexpected and unlikely occurrence. Its function is generally to resolve an otherwise irresolvable plot situation, to surprise the audience, to bring the tale to a happy ending, or act as a comedic device.
More next time the spirit moves me.