The etymology of the word “irregular” traces back to the Latin word “irregularis.” This term is composed of two parts: “in-” meaning “not,” and “regularis,” which means “rule” or “pattern.” “Regularis” itself comes from “regula,” which signifies “rule.” Therefore, “irregular” originally meant “not according to the rule.” Over time, this Latin term evolved into the English “irregular,” retaining its fundamental meaning of something that does not follow the usual rules, patterns, or norms.