What does "briar" mean?

Briar: A plant with a slender woody stem bearing stout prickles; especially, species of Rosa, Rubus, and Smilax.

Additional senses

  1. 2.Fig.: Anything sharp or unpleasant to the feelings. The thorns and briers of reproof. Cowper. Brier root, the root of the southern Smilax laurifolia and S. Walleri; -- used for tobacco pipes. -- Cat brier, Green brier, several species of Smilax (S. rotundifolia, etc.) -- Sweet brier (Rosa rubiginosa). See Sweetbrier. -- Yellow brier, the Rosa Eglantina.

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