atelectasis

noun

at·​el·​ec·​ta·​sis ˌa-tə-ˈlek-tə-səs 

plural atelectases ˌa-tə-ˈlek-tə-ˌsēz 

: collapse of the expanded lung

also : defective expansion of the pulmonary alveoli at birth

Examples of atelectasis in a Sentence

Recent Examples on the Web

Having small amounts of atelectasis is typically OK, especially if the alveoli can readily get re-inflated again. — Bruce Y. Lee, Forbes.com, 20 Mar. 2026

Word History

Etymology

borrowed from New Latin (in the phrase atelectasis pulmonum "incomplete dilatation of the lungs"), from Greek atelḗs "incomplete, unsuccessful" (from a- a- entry 2 + -telēs, adjective derivative of télos "fulfillment, completion, goal") + New Latin ectasis "expansion of a hollow or tubular organ, dilatation," borrowed from Greek éktasis "stretching out, extension" (action noun from ekteínein "to stretch out, extend"), from ek- ec- + tásis "stretching, tension" — more at telos, tenant entry 1

Note: The term was introduced by the German physician Eduard Jörg in De morbo pulmonum organico ex respiratione neonatorum imperfecta orto (Leipzig, 1832).

First Known Use

1837, in the meaning defined above

Rhymes for atelectasis

• bronchiectasis
• homeostasis
• anabasis
• cholestasis
• haemostasis
• hemostasis
• hypostasis
• periphrasis
• basis
• glacis
• mesas
• stasis

Medical Definition

atelectasis

noun

at·​el·​ec·​ta·​sis ˌat-ᵊl-ˈek-tə-səs 

plural atelectases -ˌsēz 

: collapse of the expanded lung

also : defective expansion of the pulmonary alveoli at birth

atelectatic

-ek-ˈtat-ik 

adjective