| major(severe, big, important, substantial, grand) |
| marked(big, significant, substantial, valuable, vital) |
| massive(big, large, huge, immense) |
| material(big, important, significant, substantial, valuable) |
| mattering much(expression, big, significant, substantial, valuable) |
| meaning business(expression, adjective, tough, severe, important) |
| memorable(important, significant, historic) |
| necessary(big, significant, substantial, valuable, vital) |
| no end of(expression, idiom) |
| no joke(expression, adjective, tough, severe, important) |
| no laughing matter(expression, adjective, idiom, tough, severe) |
| no stone unturned |
| of consequence(expression, adjective, tough, severe, important) |
| of great scope |
| of moment(expression, big, important, significant, substantial) |
| of note(expression, big, significant, substantial, valuable) |
| of substance(expression, big, significant, substantial, valuable) |
| operose(adjective, tough, severe, important, significant) |
| out-and-out(great, complete, intense, grand, thorough) |
| out for blood(expression, adjective, idiom, tough, severe) |