"Plugged Nickel" is the title of today's crossword by Don Gagliardo and C.C. Burnikel. In the United States, the five-cent coin we call a nickel was originally pure silver. Nickel coins minted since 1946 have contained 75% copper and 25% nickel. The expression "Not worth a plugged nickel" means "worthless" or "valueless." Back in the days when the nickel coin was pure silver, con men would drill a fairly large hole through the center of a nickel and then fill the hole with an inferior metal. Thus, they could spend the "plugged nickel" and retain the silver from the center. After they accumulated enough of those centers, they could sell the silver for extra cash.
And today's crossword has absolutely nothing to do with any of that.
Nickel is a silver-white metal. The word comes from the German
Kupfernickel, which literally means "copper goblin" and refers to a mineral called niccolite. The mineral contains nickel arsenide but has the color of copper. I'm not sure how the deceptive color is similar to a goblin, so please don't ask. The symbol for nickel is "Ni" and each theme answer in today's puzzle is a common term with the letters NI inserted -- or, you could say, "plugged."
Sweet tooth? SUGARCANINE
Signal that nails are dry? MANIBELL
Rejection of a parcel? PACKAGEDENIAL
Flier with a magical rod? DIVININGBIRD
Ace garage door mechanic? GENIEWHIZ
Part of the ad that sells the product? FINISHINGHOOK
Superhero who doesn't do well in a crisis? PANICMAN
Carrier pigeon's daily delivery? NEWSCANISTER
Nocturnal critter enjoying a meal? DININGBAT
Ralph Lauren's
Celebrate Radio clothing line? MARCONIPOLO
That last one is a reference to Guglielmo Marconi (1874-1937), an Italian inventor and electrical engineer whose pioneering work in wireless telegraphy and long-distance radio communication earned him the unofficial title "The father of radio." Marco Polo (1254-1324) was an Italian merchant who traveled extensively in Asia. The polo shirt was introduced in 1972 by fashion designer Ralph Lauren. It was a knit shirt with a collar and a placket with two or three buttons and it resembled the shirts that had traditionally been worn by polo players. History.com has a simplified story of Marconi's life and his invention of radio:
http://www.history.com/topics/inventions/guglielmo-marconi
