| Answer | Crossword Clue |
|---|---|
| unsurpassable | Not able to be exceeded in quality or degree |
| unbeatable | Not able to be defeated or exceeded in a contest or commercial market |
| reliable | Consistently good in quality or performance; able to be trusted |
| inconvertible | Not able to be changed in form, function, or character |
| nonproductive | Not producing or able to produce goods, crops, or economic benefit (tending to be less forceful in meaning than unproductive) |
| superheat | to heat (a gas, as steam not in contact with water) to such a degree that its temperature may be lowered or its pressure increased without the conversion of any of the gas into liquid |
