means The practice of keeping something within reasonable limits — neither too much nor too little — especially in eating, drinking, or behavior.

from From Latin moderatio, 'a controlling, guiding, keeping within bounds,' from moderari, 'to regulate or restrain.' The root is tied to modus, 'measure' — the same measure that gives us 'mode,' 'modest,' and 'modify.' At its heart sits the idea of fitting things to their proper measure: not the absence of appetite, but the act of holding it on a leash.