In the 2012 Doctor Who Christmas special The Snowmen Vastra gives the Clara of that time the One Word Test to which her answer to Vastra's final question, to give the Doctor a message but with just one word, was "Pond".
We know that this Clara is one of many that created and spread throughout The Doctor's Timeline when she entered it in his tomb on Trenzalore. However this Clara did not know who The Doctor was so I am wondering if she understood the meaning of the word "Pond" to the Doctor as opposed to what she may have thought what it meant?