Whiskers are generally found, of course, on the faces of animals (though, confusingly, the cat's whiskers are exactly the same as the bee's knees).
Some birds, various prawn-like creatures, and bats have whiskers, and many non-flying mammals do, too.
Whiskers have the lovely anatomical name vibrissa, which is to do with vibrating, but they're mostly used as feelers - except in the case of humans, where whiskers are usually an attempt to excuse odd behaviour.
In chemistry, a whisker is a very fine single crystal, often surprisingly strong and good at conducting electricity.
There are also whisker booms, which hold extra sails on a boat when there's not much wind.
And of course a whisker also means a tiny distance, as in when the custard exploded I escaped death by a whisker.
Word To Use Today: whisker. This word comes from the Old Norse word visk, which means wisp, and before that from the Old High German wisc.