What is the formal definition of savory?
In cooking, "Savory" does generally refer to a flavor profile that is anything other than sweet.

"Sweet" doesn't have to necessarily be sugary sweet...basil, tarragon, fennel, carrots, beets, etc. have sweet flavors that are not excessively sugary sweet.

The term "neutral" is typically used for things like crepes and choux paste (eclair paste) because when made in their traditional style they are neither savory nor sweet and can work with either flavor profile.