plank vs flump

plank is a noun but flump is not a noun.

Word	Noun	Adjective	Verb	Adverb
plank	Yes	No	Yes	No
flump	No	No	Yes	No

As verbs, plank and flump are synonyms defined as:

plank and flump: set (something or oneself) down with or as if with a noise

Other synonyms of plank include plonk, plop, plump, plump down, plunk, plunk down.

plank (noun)	flump (noun)
an endorsed policy in the platform of a political party
a stout length of sawn timber; made in a wide variety of sizes and used for many purposes

plank (verb)	flump (verb)
cook and serve on a plank	set (something or oneself) down with or as if with a noise
cover with planks	fall heavily
set (something or oneself) down with or as if with a noise