pĕr-ācer

ācris, ācre, adj.
I. very sharp; trop.: judicium, Cic. Fam. 9, 16, 4 (but in Plaut. Bacch. 3, 3, 1, the correct reading is cor acre; v. Ritschl ad h. l.).
Lewis & Short
A Latin Dictionary, 1879
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