| The Depression and others | 25 |
| The Cenozoic and others | 23 |
| The Bush years, both of them | 28 |
| Stats for Walk and Waits | 24 |
| Some timeline divisions | 23 |
| Some aces have low ones | 23 |
| Significant stretches of time | 29 |
| Reagan and Clinton, e.g. | 24 |
| Prominent periods of history | 28 |
| Prohibition and Precambrian | 27 |
| Presidential terms, perhaps | 27 |
| Presidential terms, e.g. | 24 |
| President's term, e.g. | 26 |
| Presidencies may define them | 28 |
| Precambrian and Progressive | 27 |
| Precambrian and others | 22 |
| Postwar period and others | 25 |
| Periods worth remembering | 25 |
| Periods of distinction | 22 |
| Periods for geologists | 22 |
| Paleozoic amd Mesozoic | 22 |
| Oft-named time periods | 22 |
| Noteworthy stretches of time | 28 |
| Noteworthy periods of time | 26 |
| Napoleonic and depression | 25 |
| Memorable spans of time | 23 |
| Memorable periods of time | 25 |
| Memorable periods of history | 28 |
| Many presidential periods | 25 |
| Macedonian and Mohammedan | 25 |
| Macedonian and Mayan, e.g. | 26 |
| Long lines on a timeline | 24 |
| Jazz and swing periods | 22 |
| Important stretches of time | 27 |
| Important historical periods | 28 |
| History book sections, say | 26 |
| Historic periods of note | 24 |
| Historic blocks of time | 23 |
| Historians' subjects | 24 |
| Emperor's reigns, e.g. | 26 |
| Edwardian and gaslight | 22 |
| Diamond figures: Abbr. | 22 |
| Depression and Prohibition | 26 |
| Deadball and steroid, e.g. | 26 |
| Concerns for Cone and Rivera | 28 |
| Clinton and Bush, for two | 25 |
| Climatologist's times | 25 |
| Christian and Paleozoic | 23 |
| Christian and Muslim periods | 28 |
| Christian and gaslight | 22 |
| Christian and Elizabethan | 25 |
| Chapters in world history | 25 |
| Chapters in social studies | 26 |
| Chapters in a history book | 26 |
| Certain historical spans | 24 |
| Cenozoic and Paleozoic, e.g. | 28 |
| Big historical periods | 22 |
| Big band and Roman, e.g. | 24 |
| Augustan and Caesarean | 22 |
| Archeozoic, Paleozoic, etc. | 27 |
| Archeozoic and Cenozoic | 23 |
| Alexandrian and Napoleonic | 26 |
| Alexandrian and Babylonian | 26 |
| Alexandrian and Augustan | 24 |
| Actian and Alexandrian | 22 |
| "-zoic" periods | 25 |
| Like some typing paper | 22 |
| Unlocked, as a computer file | 28 |
| Subject to being wiped out | 26 |
| Like some wall calendars | 24 |
| Like some compact discs | 23 |
| Like slates and hard drives | 27 |
| In pencil, for example | 22 |
| Answering machine button | 24 |
| Demagnetize, as a tape | 22 |
| Shake an Etch A Sketch, e.g. | 28 |
| Shake an Etch A Sketch | 22 |
| Clear, as a blackboard | 22 |
| Answering-machine button | 24 |
| Clear, as a chalkboard | 22 |
| Use the unsharpened end | 23 |
| Clear, as a hard drive | 22 |
| Totally eliminate, in a way | 27 |
| Shake, as an Etch A Sketch | 26 |
| Shake an Etch-a-Sketch | 22 |
| Remove, as pencil marks | 23 |
| Remove from the blackboard | 26 |
| Prepare for reuse, perhaps | 26 |
| Invert one's pencil | 23 |
| Invert and use a pencil | 23 |
| Get rid of a voicemail | 22 |
| Empty the Recycle Bin, e.g. | 27 |
| Destroy a recording, in a way | 29 |
| Clean, as a flash drive | 23 |
| Clean, as a blackboard | 22 |
| Clean off the chalkboard | 24 |
| Backspace, on a computer | 24 |
| Wipe off the blackboard | 23 |
| Wipe off a chalkboard, say | 26 |
| What expert typists seldom do | 29 |