Legal definitions in the end are trying to turn a hammer into a scalpel.
They don't fucking matter for moral judgments.
Israel is committing a genocide to anyone with even a highschool level knowledge of history. Want a simple definition that is very effective?
Any government that intentionally withholds food, medicine, and potable water from a population it considers undesirable is intentionally committing genocide.
Starvation is historically the most effective method and most used method of committing genocide. Everyone knows what the outcome is. Anyone trying to use legal definitions at this point is an asshole genocide denier trying to pretend they're not.