Question: I would like to know the origin of the term "au pair" to describe a person, usually a young woman, hired to care for children. I see it often but have never seen an explanation.
Answer: "Au pair" entered English as a noun just within the past 40 years. The term wasn't unknown before that, but its occasional earlier use by English speakers in the past century and in the early part of this century was as an adjectival or adverbial phrase, as in "She is seeking a position au pair," which closely reflects the original French use. In French the phrase means literally "at par," but it might be best translated as "on equal terms." (The French word "pair" is ultimately derived from Latin "par," meaning "equal.") This is in reference to the reciprocal arrangement under which an au pair is usually engaged.
Nowadays, an au pair works for a family in return for room and board and a small salary, but in the past there were other types of au pair arrangements as well, such as an English girl's exchange of foreign language classes for teaching English at a French school. Some au pair exchanges may even have involved two families whose daughters exchanged places for a short time to learn each other's language. However, though some have interpreted it so, there's no evidence that "pair" was ever intended to mean "equal" in the sense of equal treatment as a member of a family.
"Au pair" became an English noun when the British picked up the continental au pair system to supply their homes with affordable domestic help after World War II. Foreign girls were willing to work for no more than room and board and pocket money since the arrangements gave them an opportunity to learn English.
Just as in England, "au pair" in the United States usually refers to a young foreign woman. While adopting "au pair," we've also picked up on the British term "nanny" to use for a usually older woman, whether foreign or American, who has similar duties but whose job specifically involves child care. An au pair isn't necessarily in charge of children, though in the United States she frequently is.
Question: I'm curious about the verb "stanch," meaning "to stop the flow of," and the adjective "staunch," meaning "steadfast." It seems to me that I have at times run across the verb spelled (or misspelled) with a "u" and the adjective spelled (or misspelled) without "u." Can you explain?
Answer: The verb "stanch" and the adjective "staunch" have much in common. Not only do both derive from the Old French verb "estancher" (which also means "to stop the flow of"), but, as you point out, the spelling "staunch" is sometimes used for the verb and the spelling "stanch" is sometimes used for the adjective. These spelling variants have been in reputable use for centuries. "Stanch" is the most common form of the verb and "staunch" is the most common form of the adjective, but the variants are also perfectly standard. The connection between the two words is perhaps more obvious when you know that the adjective "staunch" in its oldest sense means "watertight" or "sound," as in "a staunch ship."
Question: I recently stumbled upon the curious expression "to sow dragon's teeth." Can you tell me what this expression means and where it comes from?
Answer: "To sow dragon's teeth" means "to sow seeds of conflict or strife." For example, a politician who opposes an economic embargo against a foreign country might claim that the action would only "sow dragon's teeth" and perhaps even lead to war, or a gossip engaged in spreading vicious rumors might be accused of "sowing dragon's teeth" and disrupting the social fabric of the community. The phrase alludes to a story involving the legendary Greek hero Cadmus, who is reputed to have founded Thebes and invented the alphabet. According to the tale, Cadmus killed a dragon and planted its teeth in the ground. From the teeth sprang fierce armed men who battled one another until all were dead but five. These five founded the noblest families of Thebes and helped build its citadel.