"Solodant" is quite simply the same as "Themodist" on Aeolian products.
It's a method for "accenting" or "theme-ing" a note or group of notes
-- in other words, to make them somewhat more pronounced (or louder)
than the accompanying (accompaniment) notes.  You will find Solodant on
Wilcox and White products.  Possibly elsewhere.

Robin Pratt