Here are some language-related items I picked up from my recent reading:
Oslo: Harry Hole, the protagonist in Jo Nesbø's crime novel Nemesis, explains the origins of Norway's capital city's name to a visitor, "The 'Os' of Oslo means 'ridge,' the hillside we're sitting on now. Ekeberg Ridge. And 'lo' is the plain you can see down there."
Thus, Oslo means simply ridge-plain. Quite a number of place names, like River Road or Lakeville, are little more than descriptions of local geography. These names sound much more exotic in another language. Cuyahoga, an Iroquois word, means nothing more than "crooked river." Most rivers are crooked, however, so Clevelanders are probably happy to with Cuyahoga River.
Inner wear: Ever notice that we wear underwear and outerwear? Why not innerwear and outerwear or underwear and overwear? In Victorian London, Liza Picard informs us that in Victorian times they did speak of inner wear. Somehow this more logical term got lost over time.
The whole nine yards: This common expression, which became the title of an amusing Bruce Willis movie several years ago, basically just means "the whole thing." Writing in his Dwight D. Eisenhower biography, Ike: An American Hero, Michael Korda says the phrase dates only from World War II. The belts of .50-caliber ammunition for the machine guns on American bombers were 27-feet long. When gunners had fired "the whole nine yards," it was time to reload.