Happy As a Clam

Origin:

There's two versions of this phrase. The full version is "as happy as a clam at high tide [or water]," and then there's the shorter version "as happy as a clam." Why, though, would a clam would be "happy" in the first place? Well, the reason for that is actually highlighted in the full version of this expression.

Basically, clams are most vulnerable when the tides are low because that's the time when people can easily dig them up out of the ground. In higher waters, however, clams are far more difficult to find and dig up. Hence, a clam is "happiest" during a high tide, or high waters, because it means they are less likely to be caught and eaten!

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