authoritative.

1. Recognized as knowledgeable or reliable enough to settle a question.

2. Showing assured authority in speech or behavior.

Use it for

Words that belong together

• authoritative source
• authoritative account

On the page

The archive provides an authoritative account of the negotiations.

Usage notes

Primary category: academic / formal. Forms: Comparative more authoritative; superlative most authoritative 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. Writing functions: analysis, evaluation. Commonness: moderately common.