Suffering from illness or not working properly; in poor health or condition.
From Middle English 'ailen,' possibly from Old English 'eglan' meaning to trouble or afflict. The '-ing' suffix marks it as a present participle used as an adjective.
The word 'ailing' is interesting because we use it for both people ('an ailing grandmother') and systems ('an ailing economy'), showing how metaphorically we treat countries and institutions as if they were bodies that can get sick.
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