Synonyms that are in the dictionary are marked in green. Synonyms that are not in the dictionary are marked in red.
Antonyms that are in the dictionary are marked in green. Antonyms that are not in the dictionary are marked in red.
Google Ads offers a tool called Keyword Planner that they make available to anyone with an active Google Ads account.
Source: https://www.forbes.com/sites/forbesagencycouncil/2023/04/20/the-fundamentals-of-keyword-research/