A sudden involuntary drop to the ground:
dive, fall, pitch, plunge, spill, tumble. (Informal) header. See riseThe act of plunging suddenly downward into or as if into water:
dive, plunge, swoop. (Informal) header. See enterA usually swift downward trend, as in prices:
decline, descent, dip, dive, downslide, downswing, downtrend, downturn, drop, drop-off, fall, plunge, skid, slide, slump, tumble. See increase
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