unsustainable.

Unable to be maintained over time or supported by adequate reasons.

Use it for

Words that belong together

• unsustainable burden
• unsustainable claim

On the page

The workload was unsustainable for a team of four.

Usage notes

Primary category: analysis / argumentation / evidence. Forms: Comparative more unsustainable; superlative most unsustainable when comparison is meaningful. Legacy lexical fields mirror sense 1 only. Use numbered sense fields for all meanings. Established modern English lexical item. No separate regional spelling or grammatical inflection entry. Commonness: moderately common.