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unputdownable

American  
[uhn-poot-dou-nuh-buhl] / ˌʌn pʊtˈdaʊ nə bəl /

adjective

Informal.
  1. (especially of a book or periodical) so interesting or suspenseful as to compel reading.


unputdownable British  
/ ˌʌnpʊtˈdaʊnəbəl /

adjective

  1. (of a book, esp a novel) so gripping as to be read right through at one sitting

"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

Etymology

Origin of unputdownable

From phrase put down; see un- 1, -able