| One-year record | 15 |
| One-year prison term, in slang | 30 |
| One-year plants | 15 |
| One-word question from Miss Piggy | 33 |
| One-word question | 17 |
| One-word query | 14 |
| One-word defs. | 14 |
| One-word def. | 13 |
| One-word Built to Spill song | 28 |
| One-word bird? | 14 |
| One-word bird in a poem | 23 |
| One-word advice to the Graduate | 31 |
| One-word advice | 15 |
| One-wheeled vehicles | 20 |
| One-wd. definition, essentially | 31 |
| One-wd. definition | 18 |
| One-way-traffic enforcer, often | 31 |
| One-way transports? | 19 |
| One-way transports | 18 |
| One-way transporters | 20 |
| One-way symbol | 14 |
| One-way street sign symbol | 26 |
| One-way street sign | 19 |
| One-way street no-nos | 21 |
| One-way street no-no | 20 |
| One-way sign shape | 18 |
| One-way sign | 12 |
| One-way indicator | 17 |
| One-way flights? | 16 |
| One-volume works of Shakespeare, e.g. | 37 |
| One-volume encyclopedia range | 29 |
| One-ups a card | 14 |
| One-ups | 7 |
| One-upped, in a way | 19 |
| One-upped | 9 |
| One-upmanship on the set | 24 |
| One-up with smarts | 18 |
| One-up trick | 12 |
| One-up the duchess? | 19 |
| One-up tactics | 14 |
| One-up tactic | 13 |
| One-up maneuver | 15 |
| One-up job | 10 |
| One-up at the poker table, maybe | 32 |
| One-up | 6 |
| One-two's one | 17 |
| One-two wager | 13 |
| One-two track options | 21 |
| One-two target | 14 |
| One-two subject | 15 |
| One-two punch leadoff | 21 |
| One-two part, sometimes | 23 |
| One-two part | 12 |
| One-two link for Welk | 21 |
| One-two in the ring? | 20 |
| One-two connector | 17 |
| One-two bet | 11 |
| One-twentieth of MMMXX | 22 |
| One-twentieth of an old franc | 29 |
| One-twentieth of a ton (abbr.) | 30 |
| One-twentieth of a shekel | 25 |
| One-twentieth of a franc, once | 30 |
| One-twelfth of the AA program | 29 |
| One-twelfth of a pica | 21 |
| One-twelfth of a gross | 22 |
| One-twelfth of a foot | 21 |
| One-trillionth: Comb. form | 26 |
| One-trick ___ | 13 |
| One-track transport | 19 |
| One-track | 9 |
| One-touch phone feature | 23 |
| One-touch convenience | 21 |
| One-toothed dragon of old children's TV | 43 |
| One-ton beast | 13 |
| One-to-one, e.g. | 16 |
| One-to-one learner | 18 |
| One-to-nine items | 17 |
| One-time, once | 14 |
| One-time Yukon capital, ___ City | 32 |
| One-time Yugoslavian president | 30 |
| One-time Yugoslavian | 20 |
| One-time Yugoslav leader | 24 |
| One-time Yugoslav chief | 23 |
| One-time YouTube sensation Zonday | 33 |
| One-time Yankees manager | 24 |
| One-time word processors | 24 |
| One-time word in a marriage vow | 31 |
| One-time Winter Palace occupant | 31 |
| One-time Winter Palace dwellers | 31 |
| One-time Wimbledon winner | 25 |
| One-time wife of Mickey and Frank | 33 |
| One-time wife of Mickey | 23 |
| One-time wife of Frank Sinatra | 30 |
| One-time White House nickname | 29 |
| One-time water source | 21 |
| One-time Washington Senator hopeful | 35 |
| One-time Wall St. watchdog | 26 |
| One-time video game sensation | 29 |
| One-time ventilator used in fighting polio | 42 |
| One-time Venetian coin | 22 |