What defines an object that has equal numbers of protons and electrons?

An object that has equal numbers of protons and electrons is classified as a neutral object. This is because protons carry a positive charge, while electrons have a negative charge. When these two charges are in balance, the overall charge of the object is zero, indicating that it is neutral.

In contrast, if there were more protons than electrons, the object would be positively charged, and if there were more electrons than protons, it would be negatively charged. The term "charged object" generally refers to any object that has an imbalance between its protons and electrons, whether it is positively or negatively charged. Therefore, the defining characteristic of neutrality is the equal presence of protons and electrons, leading to an overall charge of zero.