p-KKkkkkkkkk.

(also p-KKkkkkkkkkk.)  n.  the sound of “waves breaking,” as in the novel The Wild Shore: Three Californias by Kim Stanley Robinson.

p-p-p.

n.  the patter of cat feet, as described in Wishes, Lies, and Dreams: Teaching Children to Write Poetry by Kenneth Koch.

Pb-pb-b-b-b.

n.  the sound that powers a miniature motorcycle.

<Next he inhaled deeply and with a Pb-pb-b-b-b sound, the only sound that will make a miniature motor-cycle go, sped out from under the television set and across the carpet.  Pb-pb-b-b-b!  Ralph rode across the lobby.  —Beverly Clearly, Runaway Ralph.>

pbbbtt.

n.  the sound of a sudden expectoration, as upon being surprised while sipping tea in the graphic novel Flipside by Brion Foulke.

pf.

n.  the whimper at the end of the world.

<If he escapes ... the world is over.  Pf!, like that.  —Neil Gaiman, American Gods.>

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