Nouns

(n)plumpthe sound of a sudden heavy fall

Verbs

(v)plummet, plumpdrop sharply“The stock market plummeted”
(v)plank, flump, plonk, plop, plunk, plump down, plunk down, plumpset (something or oneself) down with or as if with a noise“He planked the money on the table”, “He planked himself into the sofa”
(v)fatten, fat, flesh out, fill out, plump, plump out, fatten out, fatten upmake fat or plump“We will plump out that poor starving child”
(v)plump, gogive support (to) or make a choice (of) one out of a group or number“I plumped for the losing candidates”

Adjectives

(s)chubby, embonpoint, plumpsufficiently fat so as to have a pleasing fullness of figure“a chubby child”, “pleasingly plump”

Adverbs

(r)plumpstraight down especially heavily or abruptly“the anchor fell plump into the sea”, “we dropped the rock plump into the water”