| Not outgoing | 12 |
| Not outdoors | 12 |
| Not out-of-bounds, as a ball | 28 |
| Not out on the town | 19 |
| Not out of the sack yet | 23 |
| Not out of the sack | 19 |
| Not out of the running | 22 |
| Not out of the question | 23 |
| Not out of the house | 20 |
| Not out of style? | 17 |
| Not out of place | 16 |
| Not out of one's mind | 25 |
| Not out of it | 13 |
| Not out of contention | 21 |
| Not out and about | 17 |
| Not out | 7 |
| Not ours | 8 |
| Not our | 7 |
| Not otherwise classified (Abbr.) | 32 |
| Not otherwise categorized (Abbr.) | 33 |
| Not ostensible | 14 |
| Not ornate | 10 |
| Not originals of letters, for short | 35 |
| Not originals | 13 |
| Not original: Abbr. | 19 |
| Not original | 12 |
| Not orig. | 9 |
| Not organized | 13 |
| Not ordinary: Abbr. | 19 |
| Not ordinary | 12 |
| Not ordained | 12 |
| Not oral | 8 |
| Not optional: Abbr. | 19 |
| Not optional | 12 |
| Not opt. | 8 |
| Not opt for mediocrity | 22 |
| Not opposin' | 16 |
| Not opposed t' | 18 |
| Not opposed | 11 |
| Not operator-assisted | 21 |
| Not operating properly | 22 |
| Not operating | 13 |
| Not openly | 10 |
| Not open-ended, as a question | 29 |
| Not open-ended | 14 |
| Not open, like a Broadway theater | 33 |
| Not open to the public | 22 |
| Not open now | 12 |
| Not open (to) | 13 |
| Not open | 8 |
| Not opaque | 10 |
| Not only that but also | 22 |
| Not only that | 13 |
| Not only like | 13 |
| Not oneself today | 17 |
| Not oneself | 11 |
| Not one: Dialect. | 17 |
| Not one: Colloq. | 16 |
| Not one-track | 13 |
| Not one, to Ozark Ike | 21 |
| Not one, to Jethro Bodine | 25 |
| Not one, informally | 19 |
| Not one, in Dogpatch | 20 |
| Not one, country style | 22 |
| Not one, colloquially | 21 |
| Not one, but two and four | 25 |
| Not one's cup ___ | 21 |
| Not one's brightest hour | 28 |
| Not one's best effort, in a sports metaphor | 47 |
| Not one's best effort | 25 |
| Not one ___ questions | 21 |
| Not one ___ | 11 |
| Not one to try new ideas | 24 |
| Not one to trust | 16 |
| Not one to talk? | 16 |
| Not one to take home to meet the folks | 38 |
| Not one to see it through | 25 |
| Not one to go solo | 18 |
| Not one to believe | 18 |
| Not one solid color, maybe | 26 |
| Not one or the other | 20 |
| Not one of the majors | 21 |
| Not one of the major birds | 26 |
| Not one of the Hiltons | 22 |
| Not one of the gang | 19 |
| Not one of the big dogs | 23 |
| Not one nor the other | 21 |
| Not one cent went for this | 26 |
| Not one card short of a deck | 28 |
| Not one | 7 |
| Not once, to a poet | 19 |
| Not once, poetically | 20 |
| Not once, in poetry | 19 |
| Not once, in Nürnberg | 24 |
| Not once | 8 |
| Not on ___ | 10 |
| Not on your life! | 17 |
| Not on your life | 16 |
| Not on time for | 15 |
| Not on time | 11 |