indeclinable (emphatic particle form)
Analysis. sammā + eva; sammā (adverb from sam-) + eva (emphatic particle 'indeed, very') = 'rightly indeed', 'thoroughly precisely'.
Etymology. sammā from sam- (together, completely) + -ā (adverbial ending). Sam- cognate with English 'same', Latin similis, Greek homo-; the prefix carries concrete imagery of things brought into one, unified, hence the sense of completeness and rightness that attends proper gathering. Eva is an emphatic particle (cognate with Sanskrit eva) intensifying the preceding word.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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