What is the meaning of Flounder?

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.

A bootmaker's tool for crimping boot fronts.

To act clumsily or confused; to struggle or be flustered.

To flop around as a fish out of water.

To make clumsy attempts to move or regain one's balance.

To be in serious difficulty.

Alternative form of flowndre

Source: wiktionary.org