Saltiness
Any flavor or gustatory perception that could be loosely described as something like drinking water is called a moist sensation. We use words like briny, fresh, pickled, pure, fishy, drinkable, alkaline, clean, saline, etc. to describe specific tastes in this category. The reference experience for describing moist sensations is tasting the ocean. So to make a binary description of a moist taste sensation, compare it with a sip of seawater. Report the result using one of the following algebraic statements. If a sensation cannot be compared with drinking water, then say it is not a moist sensation and write $\delta_{\sf{I}}=0$. If a sensation is like tasting the ocean, then call it a brackish taste and express this as $\delta_{\sf{I}}=+1$. If a sensation is not like tasting like the ocean, then say it is potable and report $\delta_{\sf{I}}=-1$. The number $\delta_{\sf{I}}$ is called the saltiness. And the word salty is often used as a catchall for moist sensations.

 Noun Definition Moist Sensation $\sf{\text{Any taste sensation similar to a drink of water.}}$ 1-16
 Adjective Definition Saltiness $\delta_{\sf{I}} \equiv \begin{cases} +1 &\sf{\text{if a moist taste sensation is brackish }} \\ \; \; 0 &\sf{\text{if a sensation is not moist }} \\ -1 &\sf{\text{if a moist taste sensation is potable }} \end{cases}$ 2-9