n. 25B6; verb
Joy plunged into the sea : DIVE, jump, throw oneself, launch oneself.
the aircraft plunged to the ground : PLUMMET, nosedive, drop, fall, pitch, tumble, descend.
the car plunged down an alley : CHARGE, hurtle, career, plough, cannon, tear; N. Amer. informal barrel.
oil prices plunged : FALL SHARPLY, plummet, drop, go down, tumble, slump; informal crash, nosedive.
he plunged the dagger into her back : THRUST, jab, stab, sink, stick, ram, drive, push, shove, force.
plunge the pears into water : IMMERSE, submerge, dip, dunk.
the room was plunged into darkness : THROW, cast, pitch.
25B6; noun
a plunge into the deep end : DIVE, jump, nosedive, fall, pitch, drop, plummet, descent.
a plunge in profits : FALL, drop, slump; informal nosedive, crash.
25A0; take the plunge COMMIT ONESELF, go for it, throw caution to the wind(s), risk it; informal jump in at the deep end, go for broke.