梵網經菩薩戒本疏 4.77

4.77

三、釋名者，臭穢薰則為「辛」，數類差別而為「五」，非理喰噉為「食」，防止此弊為「戒」，亦功能立名。

Third, in explaining the name: The foul and pungent is 'pungent' (xin); the enumeration of types is 'five'; eating contrary to principle is 'eating'; and preventing this defect is 'precept'. The name is also established based on its function.