Never a truer word spoken

What does the saying "Never a truer word spoken" mean, and where did it come from?!

It's plain English, although someone may have used it in a well-known literary context--it does sound a bit rhetorical. Add a verb, and it becomes, "Never has a truer word been spoken," that is, whatever has just been said is absolutely correct. You could do variations on it, such as, "No truer word has e'er been said."
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