A definition need not specify something is excluded to actually exclude something.
Scalia ’12 [Antonin Scalia and Bryan Garner; 2012; Justice on the Supreme Court of the United States; American lawyer, lexicographer, and teacher; Reading Law: The Interpretation of Legal Texts, “General-Terms Canon,” Ch. 10]
The expression of one thing implies the exclusion of others (expressio unius est exclusio alterius).
Expressio unius, also known as inclusio unius, is a Latin name for the communicative device known as negative implication. In English, it is known as the negative-implication canon. We encounter the device—and recognize it—frequently in our daily lives. When a car dealer promises a low financing rate to “purchasers with good credit,” it is entirely clear that the rate is not available to purchasers with spotty credit.