Ah Definition

ä
interjection
Used to express various emotions, such as satisfaction, surprise, delight, dislike, or pain.
American Heritage
Used to express variously surprise, delight, regret, disgust, pain, etc.
Webster's New World
abbreviation
Anno Hebraico.
American Heritage
Ampere-hour.
Webster's New World
Anno Hegirae.
American Heritage
Of the Muslim era.
Webster's New World
symbol

(metrology) Symbol for the attohenry, an SI unit of electrical inductance equal to 10−18 henrys.

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