marble
n.— «MARBLES: Small pieces of tire rubber that build up above the racing groove.» —“A racing dictionary” St. Petersburg Times (Florida) Apr. 1, 2005. (source: Double-Tongued Dictionary)
Further reading
There was a time when William Shakespeare was just another little seven-year-old in school. Classes in his day were demanding — and all in Latin. A new book argues that this rigorous curriculum actually nurtured the creativity that later flourished...
Carmen in Jacksonville, Florida, was told she was pretty as a speck of puff. The more common simile is pretty as a speckled pup or cute as a speckled pup. This is part of a complete episode.
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