While listening to a radio news broadcast, I'll frequently
hear the announcer say something like (such and such a city)
"is the epicenter of" (some human activity).

When that happens I cannot resist loudly and truculently saying
to the radio, "No, it's NOT 'the epicenter of'" (whatever.)
If someone asks what I mean, I'll explain that "epicenter"
is a technical term in earthquake science, meaning that spot
on the surface of the earth above the quake's center,
which is located perhaps two or more miles below
the earth's surface.

Now, I know perfectly well that I am engaged in a lost cause,
because the word "epicenter" has been carelessly misused so
widely that it has come to mean, in the minds of many speakers,
either just "center" or maybe something like "very center
of the center". So my correction of the speaker on the radio is
useless (or otiose, if you like) on two grounds: 1, the
meaning of "epicenter" has been irretrievably fuzzed up, so
I'm out of date, and 2, the announcer can't hear me in
any case.

Just the same, for this word and for some choice few other
words I hear, I'll "correct" the usage I hear on the radio.

Dave Oesterreich