sandhi contraction: cattāri (nom. pl. neut.) + imāni (nom. pl. neut.) = 'these four'
Analysis. cattāri 'four' + imāni 'these' (nom. pl. neut. of imaṁ); the initial i of imāni is elided and the vowels contract in sandhi to a. Common in lists and doctrinal phrases (e.g. the Four Noble Truths, cattāri ariyasaccāni).
Etymology. cattāri from PIE *kʷetu̯or- (cognate with Latin quattuor, English four, German vier, Sanskrit catvāri). The prefix imā- (these, proximal demonstrative) is from PIE *i- or *ei- (related to Sanskrit idam, Latin is, English it); -ni is the neuter nominative plural ending.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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