Q.The common name of pea is simpler than its botanical (scientific) name Pisum sativum. Why then is the simpler common name not used instead of the complex scientific/botanical name in biology?

A common name is not used in place of the scientific name because common names are inconsistent and locally variable, while a scientific name is meant to identify an organism precisely and unambiguously.

• Pea is called by many different common names in different languages and regions, so the same organism could be referred to by many different words depending on where you are.
• A scientific name such as Pisum sativum, by contrast, is intended to refer to exactly one organism, understood the same way regardless of language or region.
• This precision is essential in a discipline built around classification, where an organism's identity must be communicated unambiguously. …

A common name like "pea" may sound simpler, but that very simplicity is the problem: the same organism can be known by different common names in different languages, regions, or even different local communities within the same country. Relying on such names in a scientific discipline would make it impossible to be certain that two people discussing "pea" are even talking about the same organism.

A scientific (botanical) name such as Pisum sativum is constructed to avoid exactly this ambiguity. It is meant to refer to one, and only one, organism, and to be understood the same way by anyone studying biology, regardless of their language or location. This precision and universality is essential to a field whose whole purpose is to classify and communicate about living organisms accurately. …