| Source of maple syrup | 21 |
| Source of marine ink | 20 |
| Source of martini additives | 27 |
| Source of mescal | 16 |
| Source of mesons | 16 |
| Source of metal | 15 |
| Source of milk | 14 |
| Source of milk for chèvre | 28 |
| Source of milk for some cheeses | 31 |
| Source of milk used for Romano cheese | 37 |
| Source of mints, at times | 25 |
| Source of mirth in some cities | 30 |
| Source of misery | 16 |
| Source of misgivings | 20 |
| Source of models | 16 |
| Source of modern music | 22 |
| Source of mohair | 16 |
| Source of money that's "spread" in nine puzzle answers | 68 |
| Source of moos or baas | 22 |
| Source of more pay or more play | 31 |
| Source of morning stimulation, maybe | 36 |
| Source of most of the names in "The Lion King" | 56 |
| Source of mother-of-pearl | 25 |
| Source of much Asian irrigation | 31 |
| Source of much bell-ringing | 27 |
| Source of much blonde hair | 26 |
| Source of much cheap modern furniture | 37 |
| Source of much dorm furniture | 29 |
| Source of much family friction | 30 |
| Source of much government history | 33 |
| Source of much hard wood? | 25 |
| Source of much Indian tea | 25 |
| Source of much legalese | 23 |
| Source of much Military Channel material | 40 |
| Source of much salon noise | 26 |
| Source of much talk | 19 |
| Source of much tea from Asia | 28 |
| Source of much West Coast trade | 31 |
| Source of natural light | 23 |
| Source of natural red food coloring | 35 |
| Source of needed dough | 22 |
| Source of net receipts | 22 |
| Source of nickel | 16 |
| Source of northern exposure? | 28 |
| Source of nuclear energy | 24 |
| Source of oater drumming | 24 |
| Source of oats | 14 |
| Source of obsidian | 18 |
| Source of ocean treasure, perhaps | 33 |
| Source of oil | 13 |
| Source of oil and food | 22 |
| Source of omega-3 | 17 |
| Source of orange-red light | 26 |
| Source of ornamental plumes | 27 |
| Source of overcompensating bravado | 34 |
| Source of overhead mews | 23 |
| Source of Pablo Escobar's wealth | 36 |
| Source of paper profits? | 24 |
| Source of paper tigers | 22 |
| Source of Pará rubber | 24 |
| Source of particular irritation | 31 |
| Source of patronage jobs | 24 |
| Source of patter? | 17 |
| Source of penicillin | 20 |
| Source of pennies | 17 |
| Source of pep? | 14 |
| Source of perfection | 20 |
| Source of perspiration | 22 |
| Source of peyote | 16 |
| Source of pigs' knuckles? | 29 |
| Source of PIN money | 19 |
| Source of PIN money? | 20 |
| Source of pink applesauce | 25 |
| Source of poi | 13 |
| Source of political support | 27 |
| Source of pollution | 19 |
| Source of poop that gets scooped? | 33 |
| Source of pop-ups? | 18 |
| Source of Popeye's strength | 31 |
| Source of possible harm | 23 |
| Source of potent buttons | 24 |
| Source of power | 15 |
| Source of power for horticultural equipment? | 44 |
| Source of power for many boats | 30 |
| Source of precedents | 20 |
| Source of pressure | 18 |
| Source of pressure for bicyclists | 33 |
| Source of pressure, at times | 28 |
| Source of pressure, maybe | 25 |
| Source of pressure, often | 25 |
| Source of pressure, perhaps | 27 |
| Source of pricey peanuts | 24 |
| Source of pride | 15 |
| Source of problems | 18 |
| Source of profitable success | 28 |
| Source of protein | 17 |
| Source of pulpwood | 18 |
| Source of pulpwood and turpentine | 33 |
| Source of pumice | 16 |
| Source of quick cash | 20 |