cardinal numeral + particle (dve + api)
Analysis. dve (nom./acc. neuter dual of dvi, 'two') + api (emphatic particle 'even, also'), a sandhi contraction: dve + api > dvepi. The particle api adds emphasis or concession, often rendering 'even' or 'as many as / as few as'; here it stresses the smallness or remarkableness of the number two.
Etymology. dvi is inherited from Indo-European *dwi- (Sanskrit dvi, Greek dyo, Latin duo, English two, German zwei); api derives from *api- or *opi-, akin to Sanskrit api 'also, even' and found in Greek epi (originally 'toward, upon'). The spatial sense of api as 'leaning on, alongside' underlies its emphatic use.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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