In a manner that sheds, falls off, or is shed, especially referring to leaves or other seasonal features.
From 'deciduous' plus the adverb-forming suffix '-ly.' This term is rarely used outside scientific writing, as 'deciduously' technically describes how something exhibits the characteristic of falling away.
You almost never see 'deciduously' in real writing—it's wonderfully awkward because there's rarely a need to describe *how* something sheds. But it exists in dictionaries as a reminder that English will grammatically form adverbs from almost any adjective, even if nature rarely requires it.
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