sandhi contraction: mama + assa
Analysis. mama (my, genitive/possessive) + assa (optative of atthi, to be; would be). The contraction elides the final -a of mama before the initial a- of assa, yielding mamassa. Common in conditional and potential expressions: 'it would be for me', 'it might be mine'.
Etymology. mama < mad- (Indo-European root for 'me'; Latin meus, Greek eme, English me); assa < √as (to be; Sanskrit asti, Latin est, English is). The optative sense 'would be' develops from the basic copula.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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