How to use crucial in a sentence. Synonym Discussion of crucial. crucial - WordReference thesaurus: synonyms, discussion and more. This is the British English definition of crucial.View American English definition of crucial.. Change your default dictionary to American English. Top synonyms for crucial (other words for crucial) are critical, essential and vital. All Free. Synonyms for crucial include critical, key, pivotal, decisive, climacteric, deciding, testing, determining, important and momentous. Search crucial and thousands of other words in English definition and synonym dictionary from Reverso. Top synonym for crucial (another word for crucial) is critical. Crucial synonyms and Crucial antonyms. Synonyms for 'crucial': important, major, key, vital, significant, fundamental, central, meaningful, great, all-consuming, all-important, at stake Princeton's WordNet (0.00 / 0 votes) Rate these synonyms: crucial, important (adj) Definition and synonyms of crucial from the online English dictionary from Macmillan Education.. This thesaurus page is about all possible synonyms, equivalent, same meaning and similar words for the term crucial. Synonyms for crucial, including phrases that contain crucial: pivotal, critical, key, climacteric, decisive Crucial definition is - important, significant. What is another word for crucial? Crucial synonyms.