#1 plop n. the noise of a rounded object dropping into a liquid without a splash. wn
#2 plop v. drop something with a plopping sound. wn
#3 plop r. [plunk] with a short hollow thud; "plop came the ball down to the corner of the green". wn
#4 plop v. drop with the sound of something falling into water. wn
#5 plop v. [plank, flump, plonk, plunk, plump down, plunk down, plump] set (something or oneself) down with or as if with a noise; "He planked the money on the table"; "He planked himself into the sofa". wn
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