genitive plural relative pronoun + enclitic conjunction (sandhi form)
Analysis. yesaṃ (genitive plural of ya, 'of whom/which') + ca (enclitic 'and'), bound together by sandhi: yesaṃ + ca > yesañca with assimilation of -m to -ñ before c-.
Etymology. ya is the Pali form of Sanskrit ya-, the common Indo-European relative pronoun stem *yo- (English 'you' in its original sense of 'that which turns toward', Latin quī, Greek hó). The genitive plural ending -esaṃ (-aṃ after -es-) marks possession or relation. The enclitic ca 'and' is cognate with Latin que and Sanskrit ca, both meaning 'and'.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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