n. 25B6; verb
Jack plumped down on to a chair : FLOP, COLLAPSE, sink, fall, drop, slump; informal plonk oneself; N. Amer. informal plank oneself.
she plumped her bag on the table : PUT (DOWN), set (down), place, deposit, dump, stick; informal plonk; Brit. informal bung; N. Amer. informal plunk.
I plumped for a cream cake : CHOOSE, decide on, go for, opt for, pick, settle on, select, take, elect.