AK-48 is Nirvana's ICE x Jock Horror.
A phenotype is not a strain, a phenotype is all the noticeable traits in a plant. Anything you can taste, smell, see, etc. When you make seeds, each seed gets some genes from mom and some from dad, just like we do they show variety (they have dominant and recessive genes, hetro, and homo etc.). All this genetic code is known as a genotype.
So say you have 2 different looking plants from the same strain, you have two different phenos, and possibly two different genotypes If you cross a plant with green leaves with one with blues leaves, you might get some with blue leaves and some with green leaves, you have two different phenos. They would also be two different genotypes, meaning their DNA is different. Now this was just an example, it gets much more complicated and 50/50 blue to green is just to explain what a pheno is. Also phenos can change due to enviornment.
i.e. A plant might not show any purple traits unless it "lives" around a certain temp., this is also why clones taken from the same mother look so different if one is hydro and one is soil, they also have the same genotype (gene sequence), but they look different due to enviornmental factors, their phenotype.