Bark is a versatile English word with multiple meanings:
1. The sound a dog makes: "The dog barked at the mailman."
2. The protective outer covering of a tree: "The bark of this oak tree is very rough."
3. A type of sailing ship: "They sailed across the Atlantic in a three-masted bark."
4. To speak sharply or angrily: "The teacher barked at the noisy students."
5. In medicine, refers to certain plant barks used for medicinal purposes.