You may know it as the "pound key" or as the "number sign." It's the "#" symbol on the telephone dial, also known as the octothorp (sometimes spelled octothorpe).
Apparently, the word was coined in the 1960s by a telephone company employee who wanted a single word for the symbol. All of our sources agree that octo- refers to the eight points on the symbol, but there are many stories about the origin of -thorp.According to one story, the person who invented the word was involved in an effort to have the gold medals of the athlete Jim Thorpe returned from Sweden, so he added -thorpe to the word.
Another possibility is that -thorp is related to Old Norse thorpe (village, farm, hamlet), maybe because the symbol looks something like eight fields around a village.
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