A dusky grouse.
A dusky dolphin.
A dusky shark.
Ashen; having a greyish skin coloration.
Dimly lit, as at dusk (evening).
Having a shade of color that is rather dark.
A turban shell.
a turbine
Autofire.
Very, super, etc.; usually relating to a qualitative value (as opposed to quantitative).
Causing or relating to increased speed.
With rapidly-increasing blind levels.
To autofire.