Cf. e.g. https://en.wiktionary.org/wiki/cf.
* doc/lispref/tips.texi (Documentation Tips): Correct the meaning of
"cf.".
@item
Try to avoid using abbreviations such as ``e.g.'' (for ``for
example''), ``i.e.'' (for ``that is''), ``no.'' (for ``number''),
-``cf.'' (for ``in contrast to'') and ``w.r.t.'' (for ``with respect
+``cf.'' (for ``compare''/``see also'') and ``w.r.t.'' (for ``with respect
to'') as much as possible. It is almost always clearer and easier to
read the expanded version.@footnote{We do use these occasionally, but
try not to overdo it.}