Webster's Revised Unabridged Dictionary · 1913

Knell

Knell , noun

[Old English knel, cnul, Anglo-Saxon cnyll, from cnyllan to sound a bell; compare Dutch & German knallen to clap, crack, German & Swedish knall a clap, crack, loud sound, Danish knalde to clap, crack. Compare Knoll, n. & v.]

The stroke of a bell tolled at a funeral or at the death of a person; a death signal; a passing bell;
a warning or harbinger of, or a sound indicating, the passing away of anything; -- also called death knell. [figuratively]
The dead man's knell Is there scarce asked for who. — Shakespeare
The curfew tolls the knell of parting day. — Gray

Knell , intransitive verb

[Old English 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.
Not worth a blessing nor a bell to knell for thee. — Beau. & Fl
Yet all that poets sing, and grief hath known, Of hopes laid waste, knells in that word, “alone”. — Ld. Lytton

Knell , transitive verb

To summon, as by a knell.
Each matin bell, the baron saith, Knells us back to a world of death. — Coleridge