from
The Collaborative International Dictionary of English v.0.48
Hark \Hark\ (h[aum]rk), v. i. [OE. herken. See {Hearken}.]
To listen; to hearken. [Now rare, except in the imperative
form used as an interjection, Hark! listen.] --Hudibras.
[1913 Webster]
{Hark away!} {Hark back!} {Hark forward!} (Sporting), cries
used to incite and guide hounds in hunting.
{To hark back}, to go back for a fresh start, as when one has
wandered from his direct course, or made a digression.
[1913 Webster]
He must have overshot the mark, and must hark back.
--Haggard.
[1913 Webster]
He harked back to the subject. --W. E.
Norris.
[1913 Webster]