The Collaborative International Dictionary of English v.0.48:
Regret \Re*gret"\, v. t. [imp. & p. p. Regretted (-t[e^]d); p.
pr. & vb. n. Regretting.] [F. regretter, OF. regreter; L.
pref. re- re- + a word of Teutonic origin; cf. Goth.
gr[=e]tan to weep, Icel. gr[=a]ta. See Greet to lament.]
To experience regret on account of; to lose or miss with a
sense of regret; to feel sorrow or dissatisfaction on account
of (the happening or the loss of something); as, to regret an
error; to regret lost opportunities or friends.
Calmly he looked on either life, and here
Saw nothing to regret, or there to fear. --Pope.
In a few hours they [the Israelites] began to regret
their slavery, and to murmur against their leader.
Recruits who regretted the plow from which they had
been violently taken. --Macaulay.