"to fall or fall into with a sound like 'plop,' " 1821, imitative of the sound of a smooth object dropping into water. Related: Plopped; plopping. Thackary (mid-19c.) used plap (v.). As a noun from 1833.
plop came the ball down to the corner of the green
Pliocene
PLO
plod
plodding
plonk
plop
plosive
plot
plough
plover
plow
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