| important(adjective, significant, substantial, valuable, vital) |
| momentous(adjective, big, important, significant, substantial) |
| big(important, significant, substantial, valuable, vital) |
| big-league(significant, vital, imperative) |
| chief(big, significant, substantial, valuable, vital) |
| chips are down(expression, idiom, important, significant, historic) |
| consequential(important, significant, historic) |
| considerable(big, important, significant, substantial, valuable) |
| conspicuous(significant, vital, imperative) |
| critical(big, important, significant, substantial, valuable) |
| crucial(big, important, significant, substantial, valuable) |
| decisive(big, important, significant, substantial, valuable) |
| determining(big, significant, substantial, valuable, vital) |
| earnest(big, significant, substantial, valuable, vital) |
| earth-shaking(important, significant, historic) |
| earth-shattering(important, significant, historic) |
| epochal(important, significant, historic) |
| essential(big, significant, substantial, valuable, vital) |
| esteemed(significant, vital, imperative) |
| eventful(important, significant, historic) |