dewlap
UK[ˈdjuːlæp]US[ˈduːlæp]
n
A fold of loose skin hanging from the neck or throat of an animal, especially of cattle or certain birds.
n
A similar loose fold of skin under the chin of a person.
Etymology
The word 'dewlap' is a compound from Old English dēaw (meaning "dew") and læppa (meaning "a loose hanging piece, a flap, or the lobe of the ear"). The original, literal sense was likely "a flap or fold on which dew collects," a vivid description of the pendulous skin under the neck of cattle. Over time, the specific reference to dew faded, and the term became a standard anatomical descriptor for the feature itself. This evolution from a picturesque compound to a precise technical term is a common pattern in the history of English vocabulary.
Analysis
This is a compound word from Old English, formed from two elements that are no longer independently recognizable morphemes in modern English spelling.
Examples
The old bull had a prominent, swinging dewlap.
Certain breeds of chicken are known for their large, red dewlaps.
As he aged, a slight dewlap became noticeable under his chin.