What is (a) A genus of trees or shrubs including the willow, osier, and the like, growing usually in wet grounds. (b) A tree or shrub of any kind of willow called?

salix — (a) A genus of trees or shrubs including the willow, osier, and the like, growing usually in wet grounds. (b) A tree or shrub of any kind of willow. (Webster's 1913.)

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