The story
From super- + exponential; so called because such a function eventually exceeds the value of any exponential function.
Etymology from Wiktionary, CC BY-SA 4.0.
superexponential
Today it means: Having the properties that f(0) = 1 and ∀ g,h ≥ 0: f(g)f(h) ≤ f(g+h) . Full definition →