Some good information. Rick. So, let's see if I understand this correctly then. As an example: let's say I have a seed lot of Ariadne and I raised a batch of seedlings from it. These I would call Lilium ex-'Ariadne' or any one of the five definitions you define. Going further then, if I find two of these seedlings to be very, very similar in all aspects and, also, very similar to the parent Ariadne, I would cross them. This new group of offspring would then be called a strain of Ariadne. Is that correct?
Normally I just skip right thru your definition of phrases and just call everything a strain. I do, however select two from the first batch that greatly resemble the mother and continue from there.