per-dīlĭgens

entis, adj.
I. very diligent: homo, Cic. Q. Fr. 3, 5, 6.—Adv.: perdīlĭgenter, very diligently, Cic. Att. 1, 11, 1: complecti aliquid, id. Brut. 3, 14.
Lewis & Short
A Latin Dictionary, 1879
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