The Collaborative International Dictionary of English v.0.48:
Deplore \De*plore"\, v. t. [imp. & p. p. Deplored; p. pr. &
vb. n. Deploring.] [L. deplorare; de- + plorare to cry out,
wail, lament; prob. akin to pluere to rain, and to E. flow:
cf. F. d['e]plorer. Cf. Flow.]
1. To feel or to express deep and poignant grief for; to
bewail; to lament; to mourn; to sorrow over.
To find her, or forever to deplore
Her loss. --Milton.
As some sad turtle his lost love deplores. --Pope.
2. To complain of. [Obs.] --Shak.
3. To regard as hopeless; to give up. [Obs.] --Bacon.
Syn: To Deplore, Mourn, Lament, Bewail, Bemoan.
Usage: Mourn is the generic term, denoting a state of grief
or sadness. To lament is to express grief by outcries,
and denotes an earnest and strong expression of
sorrow. To deplore marks a deeper and more prolonged
emotion. To bewail and to bemoan are appropriate only
to cases of poignant distress, in which the grief
finds utterance either in wailing or in moans and
sobs. A man laments his errors, and deplores the ruin
they have brought on his family; mothers bewail or
bemoan the loss of their children.