The present participle of accurse; the act of cursing or damning someone.
From accurse plus the gerund/present participle suffix -ing. This form allows accurse to function as both a continuous action and an adjective describing something curse-like.
The -ing form is one of English's most flexible inventions—the same word 'accursing' can be a noun (the accursing of enemies), a verb (they were accursing him), or even an adjective (an accursing fate)!
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