Causing shock and loss of confidence; deeply disappointing or disheartening.
The present participle of 'dismay' used as an adjective, describing something that has the quality of causing dismay. This is a productive modern form, unlike archaic 'dismayful'.
Test scores being 'dismaying' is a very modern use—we live in a world where data dismays us regularly. The shift from 'dismayful things' to 'things that are dismaying' shows how English preferred active, dynamic adjectives over static ones.
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