Something you hope not to see, but anyways, something you'd rather not actually be.
It is assumed that the purple cow would say moo, although I'm very sure it has yet to be found on the earth.
Oh dear, this rhyme's been used in an example already!
I've never seen a purple cow (stop this madness!)
and hope to never see one;
but I can tell you anyhow (I originally had this line wrong.)
I'd rather see than be one.