It's from the Oxford English Dictionary.
the entry: split
df: remove or be removed by breaking, separating, or dividing：
eg：[with obj.]the point was pressed against the edge of the flint to split off flakes.
Maybe my English really sucks, but is (are?) the definition and the example sentence a bit confusing and ambiguous? Does it mean the flakes are removed from the flint edge by breaking, or separating, or dividing(They should be flying/spraying/sprinkling away from the flint in my word)? It's somewhat awkward to me!