grammatical error

[Arnold Zwicky]

last week a friend of mine got a letter from the retirement office
of a company she'd worked for, saying that there was "a grammatical
error" in their previous mailing.  she was startled indeed to
discover that financial offices were now issuing corrections for
grammatical errors.

the letter explained that where the previous mailing referred to the
period october 1 through december 31, it should have referred to
the period april 1 through june 31.

"that's not a grammatical error," my friend complained, "that's an
error of *fact*!"

i observed that the letter writer had undoubtedly been instructed to
refer to the last quarter of the year, and had picked the calendar
year, when the company intended their fiscal year.

my friend noted that that would make it some sort of linguistic
error - having to do with word semantics - but not a *grammatical*
error.  i could not dispute this.

so, is "grammatical error" often used to cover any sort of error in
language at all?

arnold (zwicky at csli.stanford.edu)