We don't have synonyms for collectional yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are collection, correctional and collections.
(adj) :
Of or pertaining to a collection (set of items gathered together or a set of related items) or collections.
(adj) :
Of or pertaining to collecting, gathering, or grouping items together.
(adj) :
(logic) Pertaining to all elements of a collection simultaneously, rather than to the individual elements of the collection or to the collection as a whole.
(adj) :
(music) Pertaining to a collection (set of pitch classes).
(adj) :
Of or pertaining to a collection (set of items gathered together or a set of related items) or collections.
(adj) :
Of or pertaining to collecting, gathering, or grouping items together.
(adj) :
(logic) Pertaining to all elements of a collection simultaneously, rather than to the individual elements of the collection or to the collection as a whole.
(adj) :
(music) Pertaining to a collection (set of pitch classes).