In a manner that shows strong loyalty, support, or attachment; by sticking closely to or following faithfully.
From 'adherent' (one who sticks to or supports) plus the '-ly' adverb suffix. The adverbial form describes action performed in the manner characteristic of an adherent.
While rare in modern English, 'adherently' appears in older literary texts when writers wanted to emphasize loyal, devoted behavior—like saying someone 'adherently followed the tradition.'
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