| Certain means: Abbr. | 20 |
| Certain means of communication | 30 |
| Certain MDs | 11 |
| Certain mattress embroidery | 27 |
| Certain mathematicians | 22 |
| Certain mathematical planes | 27 |
| Certain math units | 18 |
| Certain math sign | 17 |
| Certain math number | 19 |
| Certain math instructor | 23 |
| Certain math class | 18 |
| Certain math | 12 |
| Certain mater | 13 |
| Certain matchmaker | 18 |
| Certain match results | 21 |
| Certain match ends: abbr. | 25 |
| Certain matériel, for short | 30 |
| Certain master's area | 25 |
| Certain master | 14 |
| Certain Massachusetts university | 32 |
| Certain mass transit route | 26 |
| Certain mason | 13 |
| Certain marsupials, informally | 30 |
| Certain marquis's activity | 30 |
| Certain marksmanship event | 26 |
| Certain marked-down item: Abbr. | 31 |
| Certain marital contracts, briefly | 34 |
| Certain marine vessel | 21 |
| Certain Marine rank | 19 |
| Certain marine mammal | 21 |
| Certain marine biologist's test? | 36 |
| Certain marcher in a parade | 27 |
| Certain marcher | 15 |
| Certain March days | 18 |
| Certain marbles | 15 |
| Certain marble | 14 |
| Certain maps | 12 |
| Certain Manitoba Indian | 23 |
| Certain Manhattanite | 20 |
| Certain man of the cloth | 24 |
| Certain man | 11 |
| Certain male sheep | 18 |
| Certain male doll | 17 |
| Certain male deer | 17 |
| Certain male chicken | 20 |
| Certain male | 12 |
| Certain majority | 16 |
| Certain major-leaguer, to a letter writer? | 42 |
| Certain major-league baseballer | 31 |
| Certain Major Leaguer of old | 28 |
| Certain Major Leaguer (Abbr.) | 29 |
| Certain major leaguer | 21 |
| Certain major | 13 |
| Certain main trunk | 18 |
| Certain main | 12 |
| Certain mailing addresses | 25 |
| Certain mail: abbr. | 19 |
| Certain mail destination: Abbr. | 31 |
| Certain mail cars: Abbr. | 24 |
| Certain maid or man | 19 |
| Certain maid | 12 |
| Certain mah-jongg player | 24 |
| Certain magazines | 17 |
| Certain madrileñas | 21 |
| Certain madrileña | 20 |
| Certain madonnas | 16 |
| Certain machinist's activity | 32 |
| Certain machinist | 17 |
| Certain machetes | 16 |
| Certain m.p.g. rating: Abbr. | 28 |
| Certain M.I.T. grads | 20 |
| Certain M.D.'s | 18 |
| Certain M.D. | 12 |
| Certain lyrics | 14 |
| Certain lyric poet | 18 |
| Certain lyric poem | 18 |
| Certain lymphocytes | 19 |
| Certain lymphocyte | 18 |
| Certain luminary | 16 |
| Certain LTE provider | 20 |
| Certain LSD medium | 18 |
| Certain low-ranking enlistee | 28 |
| Certain low-calorie cola | 24 |
| Certain Louvre works | 20 |
| Certain Louvre pieces | 21 |
| Certain Louvre hangings | 23 |
| Certain lounge frequenter | 25 |
| Certain Louisianians | 20 |
| Certain Louisianian | 19 |
| Certain Louisianans | 19 |
| Certain Louisianan | 18 |
| Certain Louisiana native | 24 |
| Certain lotion | 14 |
| Certain losing line | 19 |
| Certain loquacious birds | 24 |
| Certain lope | 12 |
| Certain loops | 13 |
| Certain looks | 13 |
| Certain lookers | 15 |
| Certain lookalike | 17 |