3rd person plural optative (potential/conditional), or possibly 3rd person plural conditional; surface form mucceyyuṁ appears to be a variant or scribal form of muceyyuṁ
Etymology. √muc, cognate with Latin movēre (move) and English move; the root sense is 'to move away, slip, release'. The optative -eyya- marks wish or potential condition.
Meanings from the Digital Pāḷi Dictionary; morphology and etymology by Claude.
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