The Collaborative International Dictionary of English v.0.48:

Knell \Knell\, v. i. [imp. & p. p. Knelled; p. pr. & vb. n.
   Knelling.] [OE. knellen, knillen, As. cnyllan. See Knell,
   n.]
   To sound as a knell; especially, to toll at a death or
   funeral; hence, to sound as a warning or evil omen.
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         Not worth a blessing nor a bell to knell for thee.
                                                  --Beau. & Fl.
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         Yet all that poets sing, and grief hath known,
         Of hopes laid waste, knells in that word, "alone".
                                                  --Ld. Lytton.
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