Present participle: executing or putting to death by guillotine; the ongoing process of using the guillotine.
From guillotine + -ing gerund/present participle suffix. As a verb form, it describes the active process of carrying out executions by guillotine.
The word 'guillotining' entered English during the 1790s French Revolution and caused such shock that it appeared in newspaper accounts and literature describing the Terror—showing how new technologies can create new vocabulary overnight.
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