The Oxford English Dictionary (OED) online has a list of common abbreviations. I found it when I wanted to know what the short form was for subscription (there are two options Subscr. or Subscript.)
However, it only includes words that are used in the OED so it doesn't have the abbreviations that recently tripped up K. She thought her friend was saying she had an 'appointment' near her, but really she was getting an 'apartment' nearby - big difference.
There is actually a bigger, better source that I should have used: Abbreviations.com