Unreasonable

How to spell unreasonable

12 letters · 4 syllables

How to pronounce unreasonable

Say the part in capitals loudest.

What does unreasonable mean?

1. adjectiveNot guided by good sense, or going beyond what is fair or moderate.

Unreasonable in a sentence

• The landlord made an unreasonable demand for three months of rent in advance.

• It is unreasonable to expect staff to answer emails at midnight.

Where does unreasonable come from?

Language of origin: Latin

This word is built on 'reason', which English took from the Old French 'reson' or 'raison' in the 1200s, and which goes back to the Latin 'ratio', meaning a reckoning, a calculation, or the faculty of the mind that weighs things up. The Latin verb behind it, 'reri', meant 'to think' or 'to reckon', so reason was literally the act of counting and judging. To this English added two of its most productive building blocks: the native prefix 'un-', meaning 'not', and the suffix '-able', borrowed through French from the Latin '-abilis', meaning 'capable of' or 'fit for'. Put together around the late 1300s, 'unreasonable' first described a person or demand not governed by sound judgement, and it later widened to cover prices, hours, and amounts that go beyond what good sense would allow. The spelling trap is the quiet middle: the 'a' in '-reason-' and the unstressed vowels of '-able' both blur to a schwa in speech, so the ear gives no help.

How the word is built

• un- (not)
• reason (sense, judgement, from Latin ratio)
• -able (capable of, suffix forming adjectives)