plummet rhymes with "comet" which falls so sharply.
Plummet sounds like Planet (something very very heavy) .. a heavy thing will fall or drop sharply.
it can be plum+met. as we seen earlier plum(b)=vertical. plummet can be MET the VERTICLE extreme limit(lower).i.e. it fell.
plummet : plunge from a summit(as simple as that)
plum(fruit)......so wen ripe it could fall sharply...
plum--palms. so spider man palms met with ground when he falls straight down from the building.
plum--palms. so spider man palms met with ground when he falls straight down from the top of building.
As plumb(lbw) in cricket means wicket FELL => drop of something
plumment sounds like commet , commet falling straight