per-dĭus

a, um, adj.

dies

I. all day long, the livelong day (post-class.): stare solitus Socrates dicitur, pertinaci statu perdius atque pernox, Gell. 2, 1, 1; App. M. 5, p. 161, 11; 9, p. 219, 23.
Lewis & Short
A Latin Dictionary, 1879
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