Most often used with within parentheses in Boolean expressions, the or operator is technically interpreted as at least one term/phrase/expression is required, more than one or all can be returned.
Example: The query ("flavor" or "aroma") and ("turmeric" or "curcumin") returns only results that contain flavor(s), aroma(s), or both and turmeric, curcumin, or both.
Note: Results containing both terms/phrases/expressions are scored higher than results containing only one.