indeclinable (sandhi form of saki + eva)
Analysis. saki (once) + eva (only, just, even) — emphatic particle eva intensifies the sense of singleness, yielding 'once and only once' or 'at that one moment'.
Etymology. saki from √sak (to be able, suffice); the sense 'once' flows from 'one occasion when [something happened]'. Cognate with Sanskrit śak- (be capable), which shares the root with English 'sake' (originally 'cause, sake = thing that matters).
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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