The phrase "water at the mouth" is typically written as "watering at the mouth" to denote excessive salivation in anticipation of something enjoyable. The pronunciation is /ˈwɔː.tər.ɪŋ ˌæt ðə ˈmaʊθ/, with the stress on the first syllable of "watering." The spelled out form "watering" reflects the use of the present participle form of the verb "water" as a gerund to function as a noun. The "at" in the phrase is pronounced /ət/, with a reduced vowel.
The idiom "water at the mouth" is used to describe an overwhelming feeling of hunger or intense desire for food. It is often used metaphorically to express extreme anticipation or eagerness for something, not necessarily limited to food. The phrase "water at the mouth" originates from the physiological response that occurs when an individual anticipates or encounters something delicious or appealing.
In a literal sense, when a person becomes hungry, their salivary glands produce more saliva in preparation for food. This extra production of saliva is known as "watering of the mouth" or "mouth-watering." Consequently, the idiom "water at the mouth" signifies this increased saliva production due to the excitement or craving for nourishment.
Figuratively, when someone is said to have water at the mouth, it implies that they are exhibiting intense desire or enthusiasm for something. This can be manifested in various domains, such as yearning for the release of a highly anticipated movie or eagerly awaiting the outcome of a competitive event. The metaphorical usage of "water at the mouth" emphasizes the strong anticipation or craving that can precede the satisfaction of a desire, akin to how a hungry individual anticipates the fulfillment of their appetite.