Sleep isn't a nootropic. This happens quite a lot with noobs. They conflate nootropics with sleep/food/water/exercise. It wouldn't be that bad, but it derails the actual subject: I.e. nootropics.
Here's a concise definition[0]:
"(of a drug) used to enhance memory or other cognitive functions"
There are other definitions. All the ones I've seen have exogenous substances as a common denominator, however.
Here's a concise definition[0]:
"(of a drug) used to enhance memory or other cognitive functions"
There are other definitions. All the ones I've seen have exogenous substances as a common denominator, however.
[0] https://en.oxforddictionaries.com/definition/nootropic