Webbed refers to a physical trait that helps animals in water. Penguins have webbed feet for better swimming.
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Not Just Ducks
While ducks are commonly known for it, other animals can also have webbed features. Otters use their webbed paws to move gracefully underwater.
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In Human Context
Humans may also have webbing, which is typically referenced in a medical or biological context. Some people are born with webbed fingers, a condition called syndactyly.