plop (
http://definr.com/plop)
n : the noise of a rounded object dropping into a liquid without
a splash
adv : (informal) with a short hollow thud; "plop came the ball
down to the corner of the green" [syn:
plunk]
v 1: drop something with a plopping sound
2: drop with the sound of something falling into water
3: set (something or oneself) down; "He planked the money on
the table"; "He planked himself into the sofa" [syn:
plank,
flump,
plonk,
plunk,
plump down,
plunk down,
plump]