adjectives
relating or belonging to or serving as a monument
"the use of the arch in monumental architecture"; "monumental sculptures"
of outstanding significance
"Einstein's monumental contributions to physics"
is similar to
important in effect or meaning
"a significant change in tax laws"; "a significant change in the Constitution"; "a significant contribution"; "significant details"; "statistically significant"
imposing in size or bulk or solidity
"massive oak doors"; "Moore's massive sculptures"; "the monolithic proportions of Stalinist architecture"; "a monumental scale"