I don't want to become a word maven, but sometimes I get rather annoyed at linguistic abuses. Here's one.
I was reading The Haskell School of Expression this evening, when my eyes lit on the following phrase on page 144: "Instead of pushing this line of reasoning further, let's pursue a different tact based on the (valid) assumption that if m is even, then: m = m `quot` 2 + m `quot` 2."
You don't need to know anything about the equation, I just included that to show the complete quote. The important point is the abuse of the word tact in this context, which I've seen more than once. This comes from people imitating the sound of a common figure of speech without understanding it's origin. "Taking a different tack", from context clearly means trying a new approach or new direction, but to the ear, and the lazy tongue, tact rolls out almost as easily.
But it's wrong! Tact and tack are short words. Even if the average person has no reason to know what a tack(line) is, or how to tack into the wind, they must surely understand the meaning of tact well enough to wonder what the heck "pursue a different tact" should mean?
Google search pursue +different +tack: 11,000 results.
Google search pursue +different +tact: 12,500 results!
The illiterate are winning!