What is the difference between mauve and lilac?

I did not get far in the hunt for miniature water in Scrapsville yesterday.  I have not found anything thus far today, but that is because I have had my fingers full of that clay I love so much and I have been creating.  Today I have been working with the lilac/mauve (I don't really know the difference between those colours except they are both related to the pink and purple family) clay I mixed a couple of days ago.  I have made Priscilla.  She is faceless at the moment.  I will work on that later.