Definition of "Notional" :

adjective: being of the nature of a notion or concept

"To improve notional comprehension."

adjective: indulging in or influenced by fancy

"All the notional vagaries of childhood."

adjective: not based on fact or investigation

"A notional figure of cost helps in determining production costs."

adjective: not based on fact; existing only in the imagination

"To create a notional world for oneself."