Here's why:
* Abridged dictionaries are designed to provide concise definitions for common words, making them ideal for quick reference.
* Unabridged dictionaries are comprehensive and contain a wider range of words, including more specialized and archaic terms. They often provide longer and more detailed definitions, which might not be as easy to grasp quickly.
* English language legal dictionaries focus on legal terminology and wouldn't necessarily include a definition for a general word like "vanquish."
* Latin dictionaries are for translating Latin words and wouldn't offer an English definition of "vanquish."
While "vanquish" might appear in other dictionaries, an abridged English dictionary is the most likely place to find a simple and straightforward explanation.