| 100% | THYMINE | 7 | Compound paired with adenine to form DNA |
| 52% | THYMINE | 7 | The pyrimidine paired with adenine in DNA |
| 37% | INERT | 5 | Unlikely to form compounds |
| 37% | INERT | 5 | Disinclined to form compounds |
| 36% | ISOMER | 6 | Compound with multiple forms |
| 35% | THYMINE | 7 | Nucleobase that binds to adenine in DNA |
| 35% | ATTACHMENT | 10 | Form an __ to; bond with |
| 33% | BARBUDA | 7 | Coupled with Antigua to form West Indies nation |
| 33% | APE | 3 | Primate with DNA similar to humans' |
| 33% | AMMONIA | 7 | Dangerous compound to mix with bleach |
| 33% | PEN | 3 | Something to sign a form with |
| 32% | APPLIQUED | 9 | Garment covered with fabrics to form images |
| 32% | RESHAPE | 7 | To alter something's form, as one would with clay |
| 32% | META | 4 | Prefix with physics to form a branch of abstract philosophy |
| 32% | OXEN | 4 | Oregon Trail pair to ford a river with |
| 31% | ENE | 3 | Suffix with "Benz" to mean a chemical compound |
| 31% | ADO | 3 | Suffix with color to form the name of a U.S. state |
| 31% | TWEEDLEDUM | 10 | With 61-Across, a fictional pair who are hard to tell apart |
| 31% | AND | 3 | + ... with a hint to four pairs of answers in this puzzle |
| 30% | PIRATEHAT | 9 | Accessory to pair with an eye patch, maybe |
| 30% | TARN | 4 | A mountain lake formed due to rainfall that rhymes with "barn" |
| 30% | ACU | 3 | Prefix with "pressure" to mean a form of alternative medicine |
| 30% | MASONRY | 7 | Building material, bonds with mortar to form walls |
| 29% | DOUBLE | 6 | With 52-Down, betrayal, and what's formed by each pair of the trigrams |
| 29% | ASPIRIN | 7 | White crystalline compound used in the form of tablets to relieve pain |
| 29% | ACU | 3 | Prefix with "puncture" to mean a form of traditional Chinese medicine |
| 29% | ETES | 4 | Form of "to be" with "vous" |
| 29% | TIME | 4 | With 63-Across, what (in abbreviated form) has been added to the long Down answers |
| 29% | TWINNED | 7 | Paired with |
| 29% | AND | 3 | Paired with |