I wrote the question alias for cd ../.. and it doesn't accept the title: the
.. at the end always disappears.
Bug or feature?
FYI: also applies to this Meta question.
There is a bit of automated rewriting on titles, that strip punctuation other than question marks (and removes spaces before punctuation marks, too). While most of the time this goes largely unnoticed (when a title “help me i cant read my file!!!!! urgent!!!!!” gets posted as “help me i cant read my file!!!!! urgent”), it does occasionally misfire when the punctuation has a technical meaning as in your case.
However, resolution is easy in your case: you aren't trying to create an alias for
cd../.., you're trying to create an alias called
cd../... Hence my proposed title: “Can I use cd../.. as an alias name?”