Final answer:
The Boolean operator OR is used to find records that contain either or both words/phrases, thereby broadening search results.
Step-by-step explanation:
The Boolean operator that finds all records which include either or both words/phrases, and is often used with synonyms, is OR.
When using OR to connect two or more similar concepts, it broadens your results by telling the search engine that any of your search terms can appear in the results.
Boolean operators like AND, OR, and NOT are integral to database logic and mathematical sets, allowing you to link necessary information, exclude irrelevant information, and focus you search effectively.