achalasiaPronunciation: /ˌakəˈleɪzɪə/Definition of achalasia noun [mass noun] Medicine a condition in which the muscles of the lower part of the oesophagus fail to relax, preventing food from passing into the stomach. Origin: early 20th century: from a-1 'without, not' + Greek khalasis 'loosening' (from khalan 'relax') + -ia1achalasia in other Oxford dictionaries Definition of achalasia in the US English dictionary
