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atelectasis

[at-l-ek-tuh-sis]
noun Pathology.
  1. incomplete expansion of the lungs at birth, as from lack of breathing force.
  2. collapse of the lungs, as from bronchial obstruction.

Origin of atelectasis

1855–60; < New Latin; ateliosis + Greek éktasis a stretching out, equivalent to ek- ec- + ta-, variant stem of teínein to stretch + -sis -sis
Related formsat·e·lec·tat·ic [at-l-ek-tat-ik] /ˌæt l ɛkˈtæt ɪk/, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for atelectasis

atelectasis

noun
  1. failure of the lungs to expand fully at birth
  2. collapse of the lung or a part of the lung, usually caused by bronchial obstruction

Word Origin for atelectasis

C19: New Latin, from Greek atelēs imperfect + ektasis extension
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
Word Origin and History for atelectasis
n.

"incomplete expansion of the lungs," 1836, medical Latin, from Greek ateles "imperfect, incomplete," literally "without an end," (from a-, privative prefix, + telos "completion") + ektosis "extention." Related: Atelectatic.

Online Etymology Dictionary, © 2010 Douglas Harper
atelectasis in Medicine

atelectasis

[ăt′l-ĕk′tə-sĭs]
n.
  1. The absence of gas from all or a part of the lungs, due to failure of expansion or resorption of gas from the alveoli.
  2. A congenital condition characterized by the incomplete expansion of the lungs at birth.
Related formsat′e•lec•tat′ic (-ĕk-tăt′ĭk) adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.