The Collaborative International Dictionary of English v.0.48:
Harp \Harp\, v. i. [imp. & p. p. Harped (h[aum]rpt) p. pr. &
vb. n. Harping.] [AS. hearpian. See Harp, n.]
1. To play on the harp.
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I heard the voice of harpers, harping with their
harps. --Rev. xiv. 2.
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2. To dwell on or recur to a subject tediously or
monotonously in speaking or in writing; to refer to
something repeatedly or continually; -- usually with on or
upon. "Harpings upon old themes." --W. Irving.
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Harping on what I am,
Not what he knew I was. --Shak.
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To harp on one string, to dwell upon one subject with
disagreeable or wearisome persistence. [Colloq.]
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