Accusative singular neuter of idam (this, that); the final -m is the accusative ending, and the stem vowel becomes meta- before it
Analysis. metaṁ is the accusative form of the pronoun idam. The stem is id-, which becomes met- in certain cases (the u-grade ablaut), and -aṁ is the neuter singular accusative ending. This is a common oblique case form in Pali prose and verse.
Etymology. From Proto-Indo-European *i-to- (this, that), the same root as Latin iste, Old English þis (this), and Greek to (the). The -d- is the demonstrative suffix. The ablaut (id- ~ met-) reflects ancient vocalic alternations in the pronoun declension.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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