Carmine Red Vrs Red Lilac?

Could anyone explain the difference in these shades? Wouldn't the red lilac be a bit lighter?

It is in the naming of the colour I think (I am not sure myself some days).

I think when the colour is Carmine Red you can read that as saying it is Carminish Red or a shade of Red leaning towards carmine. Kind of backwards speaking or maybe I am backwards thinking.(?)

So Red Lilac would be could be read as Reddish Lilac. (?)

If I am incorrect I would appreciate correction.

The following two stamps are Canada Scott Catalogue #43, 1888 6c and #45, 1897 10c Small Queens, Ottawa printings.
6c Red Brown (or Reddish Brown). . and . . . 10c Brown Red (or Brownish Red)

Scans from ebay seller aggv http://cgi.ebay.com/CANADA-45-Mint-...em3341bc0ebf
edit added dates

Lilac belongs to the 'blue' family. It has just a tinge of red. I'd think a 'red lilac' should be the basic bluish colour, but with a bit more red than plain 'lilac'.