Of, relating to, or resembling grass; belonging to or characteristic of the grass family.
From Latin 'gramen' (grass) plus the adjectival suffix '-eous.' This variant form is slightly more common in older English botanical and agricultural texts than 'graminaceous.'
Both 'gramineous' and 'graminaceous' mean the same thing—it's one of those fun examples where English has redundant scientific terms because different botanists liked different suffixes!
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