indeclinable (sandhi form: yāva + eva)
Analysis. yāva 'as far as, up to' + eva 'just, only' — a limiting qualifier meaning 'only to the extent of' or 'merely so much as', often emphasizing the restriction of a measure or condition.
Etymology. yāva is an old interrogative-indefinite stem (related to Sanskrit yāvant- 'as many as', from the root *yā- meaning 'go' or 'reach'), and eva (from *swa 'self') serves as an intensifying particle meaning 'just' or 'only', together forming a restrictive compound common in logical and narrative contexts.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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