Splash is a variety, aka colour. It has a pale blue to white base colour marked with irregular "splashes" of dark blue.
Split means the bird carries one copy of an allele (version of a gene). Split is usually used when only one copy of a recessive allele is carried--not apparent in the bird, but known because of breeding records.
Self-blue is another variety. In the US it is synonymous with lavender, which is the name of the recessive gene cuasing the colour. In other parts of the world it means an unlaced andalusian blue (a different gene than lavender).
Typey refers the the birds body & stance, indicating that it is very good--correct for the breed. Different breeds have different body types.