Final answer:
A command in a legal information system that retrieves multiple words with the same root is called stemming. This technique helps in finding all variations of a word, thereby improving the search results within databases.
Step-by-step explanation:
The command that enables a legal information system to retrieve multiple words with the same root is called stemming
Unlike a synonym search which finds words that have similar meanings, stemming reduces words to their base or root form, enabling the retrieval of variations on that root. This technique is commonly used in search engines and legal databases to enhance the search process by increasing the chances of finding all relevant material, regardless of the specific word form used in the document.