Yes, ah is playable
...and is worth 4 points.
Found in the following dictionaries
Enable (Words with friends)
SOWPODS (Collins Scrabble Words)
OTCWL2014 (NASPA Word List 2014)
TWL06 (NASPA List 2006)
"Ah" Definition
noun
An instance of the interjection ah.
interjection
Used to express various emotions, such as satisfaction, surprise, delight, dislike, or pain.
An expression of relief, relaxation, comfort, confusion, understanding, wonder, awe, et cetera according to uttered inflection.
A word used for drama or emphasis.
A syllable used to fill space, particularly in music.
An exclamation, expressive of surprise, pity, complaint, entreaty, contempt, threatening, delight, triumph, etc., according to the manner of utterance.
pronoun
Eye dialect spelling of i., most often indicating that the speaker is using an american (particularly southern) accent.
An exclamation expressive of pain, surprise, pity, compassion, complaint, contempt, dislike, joy, exultation, etc., according to the manner of utterance.
abbreviation
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