The present participle of collogue; the act of having a private conversation or plotting together.
From collogue (to speak together). The -ing suffix forms the present participle, creating a gerund or continuous verb form that has been used since at least the 1600s in English.
English speakers in Shakespeare's time used 'collogueing' to describe the hushed conversations in castle corners—it's a word that seems to whisper its own meaning, almost onomatopoetic in how secretive it sounds.
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