Vouched-for is a common phrase that refers to something being verified or confirmed by another person. There are several synonyms that can be used to convey the same meaning, such as authenticated, validated, endorsed, attested, certified, and guaranteed. These words all imply that the information or item in question has been checked and approved by a reliable source or authority. Using synonyms for vouched-for can add variety and depth to your writing, and can help you avoid repetition. When choosing a synonym to replace vouched-for, it's important to consider the specific context and tone of your writing to ensure that the word you choose fits seamlessly into your sentence.