Definition of notional

• not based on fact; dubious; "the falsehood about some fanciful secret treaties"- F.D.Roosevelt; "a small childs imaginary friends"; "her imagined fame"; "to create a notional world for oneself"
• not based on fact or investigation; "a notional figure of cost helps in determining production costs"; "speculative knowledge"
• indulging in or influenced by fancy; "a fanciful mind"; "all the notional vagaries of childhood"