dabbrev-ignored-buffer-regexps

dabbrev-ignored-buffer-regexps is a variable defined in `dabbrev.el'.
Its value is

nil

Documentation:
List of regexps matching names of buffers that dabbrev should not check.
See also `dabbrev-ignored-buffer-names'.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 21.1 of Emacs.