Present participle of deplore: expressing strong disapproval or regret; or (as adjective) expressing disapproval or regret.
From deplore + -ing (Old English suffix forming gerunds and present participles). The -ing suffix is one of the most versatile in English.
The -ing suffix does multiple jobs: it makes verbs continuous ('I am deploring'), turns them into nouns ('Deploring injustice is important'), and creates adjectives ('with a deploring expression'), all from the same form—a remarkable economy in English grammar.
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