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unreasonable behaviour

British  

noun

  1. law conduct by a spouse sufficient to cause the irretrievable breakdown of a marriage

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

It read "WNC I want a divorce. It's not me, it's you. #Unreasonable behaviour".

From BBC

He is, though, expected to say that he doesn't condone unreasonable behaviour or language.

From BBC

A number of other allegations relating to unreasonable behaviour by Mr Byrne and pressure to work excessive hours were not upheld, the report found.

From BBC

"Those so-called sanctions on me are unreasonable, are bullying, are intentionally pressuring, trying to force me to be hesitant. But as I’ve repeatedly stressed, this unreasonable behaviour will only make me convinced that I’m doing the right thing," Lee said at a media briefing.

From Reuters

Under the old rules in England and Wales, anyone who wanted to split swiftly had to accuse their partner in a divorce petition of desertion, adultery or unreasonable behaviour.

From BBC