What does the prefix atta mean? What is it trying to abbreviate? What a? Wiktionary claims that it stands for that's a or that's the, but I do not see the resemblance to atta.
First of all, Etymonline agrees:
Merriam-Webster throws in a "probably" for good measure:
The most extended discussion I was able to find is in the Dictionary of Slang and Unconventional English by Eric Partridge:
It comes from "That's a good boy," through a series of shortenings.
protected by tchrist Mar 1 at 19:10
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