| limitation(noun, difficulty, burden, hindrance, disadvantage) |
| lock(noun, difficulty, obstacle, obstruction, impediment) |
| long row to hoe(noun, expression, idiom, business, work) |
| masher |
| maze(noun, trouble, worry, anxiety, struggle) |
| mental burden(noun, expression, trouble, worry, anxiety) |
| minding the store(noun, expression, idiom, business, work) |
| misery(noun, trouble, worry, anxiety, burden) |
| mishap(trouble, concern, strain, weight, load) |
| mission(noun, business, work, charge, burden) |
| monkey wrench(noun, expression, difficulty, obstacle, obstruction) |
| mortar and pestle(expression, idiom) |
| mountain |
| mushroom bed(expression, idiom) |
| must(noun, work, charge, concern, care) |
| need(noun, work, charge, concern, care) |
| nuisance(noun, business, work, damage, burden) |
| nutmeg grater |
| obligation(noun, work, charge, concern, care) |
| obstacle(noun, disorder, difficulty, weakness, burden) |