With the new API release, you can easily select different Retinas and get the most adequate results, whether you want to focus on context-similarity or synonym-similarity. If your goal is to disambiguate terms, i.e. identify which meanings are contained within a specific term, you will want to use an associatively focused Retina (“en_associative” in our API). If you prefer identifying synonymous items for terms or texts, then a synonymously focused Retina (“en_synonymous” in our API) will deliver better results.
More details about the two retinas are available in our FAQs.