| Prefixes meaning vapors | 23 |
| Greek for ''vapor'' | 35 |
| Clock that's sort of like a perpetual motion machine | 56 |
| ___ Energy (big natural gas utility) | 36 |
| ___ clock (self-winding timepiece) | 34 |
| It covers the earth | 19 |
| Gaseous envelope surrounding Earth | 34 |
| Bill producers, for short | 25 |
| Pat Boone's "____ Front Door" | 43 |
| Part 3 of a Neil Young lyric | 28 |
| Frost's "Tree ___ Window" | 39 |
| "Who's that knocking ___ door?" | 45 |
| "Tree ___ Window": Frost | 34 |
| "Tree ___ Window," Frost poem | 39 |
| "___ Front Door," Pat Boone's 1955 single | 55 |
| Start of some humorous comments from elders | 43 |
| "When I say so," militarily speaking | 46 |
| When some stores open | 21 |
| Copper River Indian | 19 |
| Where serve-and-volley tennis players win a lot of points | 57 |
| Where many tennis winners are hit | 33 |
| When to see Nick? | 17 |
| TV's "Nick ___" | 29 |
| Abbr. in boron's definition | 31 |
| Boron's table listing: Abbr. | 32 |
| Periodic table figs. | 20 |
| Chem. class figures | 19 |
| 1 for H and 2 for He, e.g. | 26 |
| They go from 57 to 71 in the lanthanide series: Abbr. | 53 |
| Proton counts: Abbr. | 20 |
| Periodic law figs. | 18 |
| Element info: abbr. | 19 |
| B and O figures: Abbr. | 22 |
| 92 for U and 53 for I: Abbr. | 28 |
| 7 for N, 8 for O, etc. | 22 |
| Peloponnesian War participant | 29 |
| Ugly as ___ | 11 |
| "Squat like ___ . . . ": Milton | 41 |
| "As loathsome as ___"--Shakespeare | 44 |
| Drink ___ (pledge) | 18 |
| Emissions inspector's concern | 33 |
| Double Bikini, e.g.? | 20 |
| Cornmeal | 8 |
| Thin gruel | 10 |
| Southwestern porridge | 21 |
| Mexican gruel | 13 |
| Mexican cornmeal mush | 21 |
| Latin American gruel | 20 |
| Gruel of Southwest | 18 |
| Gruel from cornmeal | 19 |
| Corn mush, down Texas way | 25 |
| Corn meal dish | 14 |
| Corn gruel | 10 |
| Cooked cornmeal | 15 |
| Cooked corn meal | 16 |
| Granada gruels | 14 |
| Island's source of revenue? | 31 |
| Superhero of 1960's TV | 26 |
| Superhero insect | 16 |
| Hanna-Barbera character | 23 |
| Ferocious Flea fighter, in cartoons | 35 |
| Diminutive Hanna-Barbera superhero | 34 |
| Character who shared top billing with Secret Squirrel in the 1960s | 66 |
| Cartoon superhero who co-headlined next to Secret Squirrel | 58 |
| Cartoon hero with antennae | 26 |
| Cartoon hero who fights Ferocious Flea and Professor Von Gimmick | 64 |
| 1960s cartoon hero with antennae | 32 |
| As silent as ___ | 16 |
| " . . . a monument, without ___": Ben Jonson re W.S. | 62 |
| Trinity debut | 13 |
| Little Boy, e.g. | 16 |
| It was used to discover fermium | 31 |
| Enola Gay's load | 20 |
| Nuclear family? | 15 |
| You definitely don't want them to drop by your house | 56 |
| Upshot of Hanks or Hulce appearing in a turkey? | 47 |
| Forster novel about the mysterious death of Tutenkhamen? | 56 |
| Director of "The Sweet Hereafter" | 43 |
| "Chloe" director, 2009 | 32 |
| With little or no warning | 25 |
| Pranks at the Bohr Institute? | 29 |
| 1970 Floyd album | 16 |
| Elementary, in a way | 20 |
| Consisting of tiny bits | 23 |
| Test ban topic | 14 |
| Fat Man, e.g. | 13 |
| Earthshaker of 1945 | 19 |
| Really spicy dessert? | 21 |
| Holder of pet electrons, protons and neutrons? | 46 |
| Extremely accurate timekeeper | 29 |
| Precise timepiece | 17 |
| P-Funk song with the line "Bow wow wow, yippee yo yippee yay" | 71 |
| 1982 George Clinton song sampled for Snoop's "What's My Name?" | 80 |
| Nuclear power | 13 |
| Subject of a 1946 act signed by Truman | 38 |
| Diablo Canyon output | 20 |
| Legislation of Aug. 1, 1946 | 27 |
| Age group (3 members) | 21 |
| It's measured in daltons | 28 |
| They're also known as daltons | 33 |