3rd person singular present indicative active of pajānāti; sāssa is an archaic/dialectal enclitic emphatic particle. The form appears to be pajānāti + sāssa, possibly with textual variation or Vedic-style emphasis.
Analysis. pa- (forward, forth, intensifying) + jānāti (knows). The prefix pa- steps forward the act of knowing, giving it the sense of distinct, thorough understanding rather than mere awareness.
Etymology. √jñā (know; cognate with English can, Latin cognōscō, Sanskrit jñāti). The prefix pa- (forward, forth) intensifies the root, as in pajānāti 'knows distinctly' — the knowledge that steps forth clearly.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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