| First meson discovered | 22 |
| First mes | 9 |
| First meetings, briefly | 23 |
| First mechanical cash registers co. | 35 |
| First mayor of N.Y.C. | 21 |
| First Mayflower passenger to set foot on Plymouth Rock, so it's said | 72 |
| First matriarch | 15 |
| First mates' home | 21 |
| First mate? | 11 |
| First mate's superior, informally | 37 |
| First mate's response to the captain | 40 |
| First mate's reply | 22 |
| First mate's greeting? | 26 |
| First mate's agreement | 26 |
| First mate of TV | 16 |
| First mate of the Pequod | 24 |
| First mate aboard the Jolly Roger | 33 |
| First mate | 10 |
| First matchmaker? | 17 |
| First mass-production auto company outside the U.S. | 51 |
| First mass-producer of cars | 27 |
| First mass-produced American car with pop-up headlights | 55 |
| First Marxist President of Chile | 32 |
| First martyr, per Matthew | 25 |
| First martyr, according to Matthew | 34 |
| First martyr in Christianity | 28 |
| First martyr | 12 |
| First marketer of Cabbage Patch Kids | 36 |
| First manuscript | 16 |
| First manned spacecraft on the moon | 35 |
| First manned ship on the moon | 29 |
| First manned mooncraft | 22 |
| First manager of the Mets | 25 |
| First man: It. | 14 |
| First man-made textile fiber | 28 |
| First man-made space satellite | 30 |
| First man-made satellite | 24 |
| First man, in Polynesian myth | 29 |
| First man, in Maori myth | 24 |
| First man, in Babylonian mythology | 34 |
| First man's sweeting? | 25 |
| First man's introduction to Eve? | 36 |
| First man to win the French Open without dropping a set | 55 |
| First man to walk in space | 26 |
| First man to be "ribbed" | 34 |
| First man to appear on the cover of Vogue | 41 |
| First man on the scene | 22 |
| First man in space | 18 |
| First man featured on the cover of the U.S. edition of Vogue | 60 |
| First man | 9 |
| First male to appear on the cover of Vogue | 42 |
| First male on the cover of ''Vogue'' | 52 |
| First maker of a mass-produced, low-priced car | 46 |
| First major-league team to sign Satchel Paige | 45 |
| First major U.S. medical school to admit women as well as men | 61 |
| First major publisher of board games in the U.S. | 48 |
| First major party female nominee for U.S. vice president | 56 |
| First major leaguer with 4,000 hits | 35 |
| First major league manager to have 2000 wins and have 2000 hits | 63 |
| First major Civil War conflict | 30 |
| First major Civil War battle on Union soil | 42 |
| First main Constitution part | 28 |
| First magnitude star in Centaurus | 33 |
| First Mac OS that used its animal codename | 42 |
| First lyricist to receive a Pulitzer Prize | 42 |
| First ltrs. | 11 |
| First ltr. | 10 |
| First Lt.'s superior | 24 |
| First Lt.'s boss | 20 |
| First loyalty, to Polonius | 26 |
| First love, perhaps | 19 |
| First love in "Abe Lincoln in Illinois" | 49 |
| First looks at Mars and Venus? | 30 |
| First look | 10 |
| First Lola in ''Damn Yankees'' | 46 |
| First livestock animal to have its genome mapped | 48 |
| First Little Pig's material | 31 |
| First little pig's building material | 40 |
| First Liston/Clay fight result, in brief | 40 |
| First lines | 11 |
| First line on many a legal document | 35 |
| First line on an IRS form? | 26 |
| First line of verse to a solver | 31 |
| First line of quote | 19 |
| First line of many puns | 23 |
| First line of “Misty” | 29 |
| First line of an ode to secretaries | 35 |
| First line of an equinoctial verse | 34 |
| First line of a Seuss classic | 29 |
| First line of a rhyme | 21 |
| First line of a nursery rhyme | 29 |
| First line of a limerick | 24 |
| First line of a couplet pertinent to this puzzle | 48 |
| First line of a "Stepquote" toast | 43 |
| First line of "Moby-Dick" | 35 |
| First lights | 12 |
| First light of day | 18 |
| First light | 11 |
| First letters | 13 |
| First letter: Abbr. | 19 |