What is (a) A shoot of a plant, springing from the root or bottom of the original stalk; a sucker. (b) A sprout or young tree that springs from a root or stump called?

tiller — (Bot.) (a) A shoot of a plant, springing from the root or bottom of the original stalk; a sucker. (b) A sprout or young tree that springs from a root or stump. (Webster's 1913.)

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