accusative singular (or nominative/accusative plural) of the adjective tiriya; likely nominalized as 'sideways being' or used adverbially
Etymology. From the root ti- ('three') with the sense of 'the third direction' (beyond up/down and forward/back), giving the sense of 'across' or 'athwart'. The form tiriyaṁ appears in the common phrase tiriyaṁ gacchati 'goes sideways/moves in the transverse direction'. No clear Indo-European cognate.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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