The meaning of MONUMENTAL is serving as or resembling a monument : massive; also : highly significant : outstanding. How to use monumental in a sentence.

MONUMENTAL definition: resembling a monument; massive or imposing. See examples of monumental used in a sentence.

In such a monumental undertaking it is inevitable that errors and inaccuracies occur.

If you describe a book or musical work as monumental, you are emphasizing that it is very large and impressive, and is likely to be important for a long time.

Definition of monumental adjective in Oxford Advanced American Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.

1. of, pertaining to, or resembling a monument. 2. exceptionally great, as in quality or degree: a monumental book. 3. of historical or enduring significance: a monumental victory.

There are eight meanings listed in OED's entry for the word monumental, three of which are labelled obsolete. See ‘Meaning & use’ for definitions, usage, and quotation evidence.