To make a sharp, loud cry or shout, often expressing pain, excitement, or surprise.
From Old English 'gielp' meaning to boast or shout. It evolved to mean any sharp cry or bark, especially used for dog sounds.
Dogs 'yelp' when they're surprised or scared, and the word has been associated with animal cries for so long that we use it for dogs instinctively, even though humans yelp too!
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