OpenEtymology

unreasonable

UKʌnˈriːz(ə)nəb(ə)lUSʌnˈriːz(ə)nəb(ə)l

Meaning

1adj

Not guided by or based on good sense; illogical or unfair.

2adj

Exceeding the limits of what is acceptable or appropriate; excessive.

Structure

word structure
1
un
not
+
2
reason
cause, logic
+
3
able
capable of

Usage

It is unreasonable to expect an answer within five minutes.

The landlord made unreasonable demands on the tenants.

The price they quoted for a simple repair was completely unreasonable.

Etymology

The word 'unreasonable' is a layered construction built upon the core concept of 'reason'. Its journey begins with the Latin ratiōnem, meaning "calculation, account, understanding," which entered English via Old French as 'reason'. The suffix '-able', from Latin -ābilis, was attached to form 'reasonable', meaning "endowed with reason" or "fair, moderate." Finally, the Old English negative prefix 'un-' was prefixed to negate the entire concept, creating a term that literally means "not capable of being reasoned with" or "not possessing sound judgment." This logical assembly from Latin and Germanic elements precisely captures the modern sense of being illogical, unfair, or excessive.

Analysis

Structure
un (not) + reason (cause, logic) + able (capable of)=unnot+reasoncause, logic+ablecapable of

- un: A prefix of Germanic origin (Old English un-), meaning "not." It functions as a negative particle. - reason: A root of Latin origin (ratiōnem, "reckoning, understanding"), functioning as the core noun meaning "logic, cause, justification." - able: A suffix of Latin/French origin (-ābilis), meaning "capable of, worthy of." It forms adjectives meaning "having the quality of."

Unreasonable Meaning, Examples & Word Origin | OpenEtymology