When discussing something that is important and should not be ignored, there are various phrases that can be used to convey this message. Some synonyms for the term "not to be overlooked" include "critical," "crucial," "significant," "essential," or "vital." These words all indicate the importance of paying attention to a particular topic or issue. Other words that can be used in place of "not to be overlooked" include "unmissable," "undeniable," or "indispensable." No matter which synonym is chosen, the message remains the same: something of great importance should not be downplayed or dismissed.