| One and one together? | 21 |
| One and one | 11 |
| One and all | 11 |
| One and a half: Comb. form | 26 |
| One among the woodwinds | 23 |
| One among the nightingales, in a poem | 37 |
| One among the moguls | 20 |
| One amok | 8 |
| One always working out | 22 |
| One always talking about his MacBook Air? | 41 |
| One always taking shots? | 24 |
| One always sticking its nose in things | 38 |
| One always snacking | 19 |
| One always seen in Häagen-Dazs? | 34 |
| One always seeing the glass half full | 37 |
| One always on the move | 22 |
| One always on the lookout for a deal | 36 |
| One always on the go | 20 |
| One always in search of himself | 31 |
| One always hoping to score | 26 |
| One alternative from Howie Mandel | 33 |
| One along an autobahn? | 22 |
| One allocating tasks, e.g. | 26 |
| One all, say | 12 |
| One alarmed in the morning? | 27 |
| One akin to a Directioner, Selenator, or Swifty | 47 |
| One airing grievances | 21 |
| One aiming at clay pigeons | 26 |
| One aiding in wrongdoing | 24 |
| One aiding | 10 |
| One aided by Nader | 18 |
| One ahead of a bishop | 21 |
| One against the odds | 20 |
| One against another | 19 |
| One against | 11 |
| One after the other | 19 |
| One after H.S.T. | 16 |
| One after congers | 17 |
| One after another? | 18 |
| One after another, as in a series | 33 |
| One after another | 17 |
| One after a decimal point | 25 |
| One after -- | 12 |
| One afraid of spiders | 21 |
| One afraid of foreigners | 24 |
| One affecting elegant expression | 32 |
| One affected by a strike | 24 |
| One advised to take two tablets | 31 |
| One advanced in years | 21 |
| One adored by philatelists? | 27 |
| One administering corporal punishment | 37 |
| One administering a Biblical punishment | 39 |
| One adjusting a shoe | 20 |
| One adjective for a leprechaun | 30 |
| One adept at table talk | 23 |
| One adept at serving | 20 |
| One adept at pulling strings? | 29 |
| One addressed as "lord" | 33 |
| One adding things up | 20 |
| One adding kick | 15 |
| One Adam Twelve, e.g. | 21 |
| One actress, or two British prime ministers | 43 |
| One actor, or two American presidents | 37 |
| One active in the heat? | 23 |
| One acting on your behalf | 25 |
| One acting on impulse? | 22 |
| One acting for another | 22 |
| One acting badly? | 17 |
| One acting badly | 16 |
| One acting | 10 |
| One across the border? | 22 |
| One across or one down, e.g. | 28 |
| One acre, e.g. | 14 |
| One accustomed to the pole position? | 36 |
| One accumulating dirt? | 22 |
| One accomplishing a great deal | 30 |
| One accepting the world as it is | 32 |
| One accepting a challenge | 25 |
| One accepted for a job | 22 |
| One abroad? | 11 |
| One abroad | 10 |
| One above the Lötschberg Tunnel | 34 |
| One above the ground | 20 |
| One above a tenor | 17 |
| One above a specialist: Abbr. | 29 |
| One about to shoot | 18 |
| One about Jerry Springer debuted in 2003 | 40 |
| One abandoned at the altar? | 27 |
| One a-courting | 14 |
| One a'courting | 18 |
| One a woman can't trust | 27 |
| One a Koufax quartet | 20 |
| One A in AMA | 12 |
| One A in aka | 12 |
| One a day, e.g. | 15 |
| One 60-trillionth of a min. | 27 |
| One 60-thousandth of a min. | 27 |
| One 13th? | 9 |
| One 13th of the month? | 22 |
| One / customer connector | 24 |