notional

Indulging in or influenced by fancy.

“all the notional vagaries of childhood”

Being of the nature of a notion or concept.

“to improve notional comprehension”

“a notional response to the question”

Not based on fact; existing only in the imagination.

“to create a notional world for oneself”

Not based on fact or investigation.

“a notional figure of cost helps in determining production costs”