Unreasonably

Unreasonably is an adverb meaning to a degree that is not reasonable, fair, or rational. It describes actions, beliefs, or conditions that exceed what is justifiable or prudent. The word is formed from the adjective reasonable with the prefix un- and the adverbial suffix -ly, tracing back to the broader family of reason and reasonableness in English.

Common uses include evaluating conduct, costs, delays, or expectations. For example, "The price is unreasonably high for a product of this quality," "The committee faced an unreasonably tight deadline," or "He was unreasonably upset by the delay." In legal and policy language, the term often appears in phrases such as "unreasonably delay" or "unreasonable search and seizure," signaling that the action lacks justification under applicable standards. In everyday language, it remains a strong evaluative term; speakers may substitute with more precise words such as excessively, unduly, or unjustified when appropriate.

Grammar: unreasonably functions as an adverb modifying verbs, adjectives, or other adverbs, as in "unreasonably difficult" or "act unreasonably." It should be used when the speaker or writer intends to express normative judgment; neutral or objective language may prefer alternatives that specify the criteria involved.

Related terms include reasonable, reasonableness, unreasonable, and unduly.