To furnish or cover with planks:
set (something or oneself) down with or as if with a noise
To drop abruptly or heavily:
Find another word for plonk. In this page you can discover 9 synonyms, antonyms, idiomatic expressions, and related words for plonk, like: plunk, plank, flump, plop, plump-down, plunk down, plump, stick-it and drop it.