flyspell-mark-duplications-exceptions

flyspell-mark-duplications-exceptions is a variable defined in `flyspell.el'.
Its value is

((nil "that" "had") ("\\`francais" "nous" "vous"))

Documentation:
A list of exceptions for duplicated words.
It should be a list of (LANGUAGE . EXCEPTION-LIST).

LANGUAGE is nil, which means the exceptions apply regardless of
the current dictionary, or a regular expression matching the
dictionary name (`ispell-local-dictionary' or
`ispell-dictionary') for which the exceptions should apply.

EXCEPTION-LIST is a list of strings. The checked word is
downcased before comparing with these exceptions.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 24.1 of Emacs.