To suffer pain.
To cause to suffer pain.
Extreme pain, either of body or mind; excruciating distress.
To be in serious difficulty.
To flop around as a fish out of water.
He gave a good speech, but floundered when audience members asked questions he could not answer well.
To make clumsy attempts to move or regain one's balance.
To act clumsily or confused; to struggle or be flustered.
A bootmaker's tool for crimping boot fronts.
A European species of flatfish having dull brown colouring with reddish-brown blotches; fluke, European flounder, Platichthys flesus.
Any of various flatfish of the family Pleuronectidae or Bothidae.