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unscheduled

British  
/ ʌnˈʃɛdjuːld /

adjective

  1. not arranged or planned according to a programme, timetable, etc

"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 was diverted to Huntingdon - an unscheduled stop - which prompted a large emergency response.

From BBC

The company said its earnings benefited from an unscheduled refund of contributions from its pension plan that lowered personnel costs and boosted its bottom line by about 50 million euros.

From The Wall Street Journal

It was diverted to Huntingdon - an unscheduled stop - where Mr Scott was waiting in the car park.

From BBC

Police received the first calls from train passengers about the incident at 19:39 GMT and soon afterwards the train was diverted to Huntingdon, an unscheduled stop on the route.

From BBC

Alexander also praised the train's driver, whose quick thinking ensured it was able to make an unscheduled emergency stop at Huntingdon in central England that allowed passengers to escape the train.

From Barron's