Belonging to or resembling the grass family, especially characteristics of reeds or reed-like grasses.
From Latin arundinaceus (reedy, of reeds), derived from arundo (reed) with the Latin suffix -aceus (relating to, having the nature of).
Scientists use this fancy word instead of 'reedy' because arundinaceous actually tells you these plants are in the same family as bamboo and wheat—all grasses with hollow stems.
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