Secret, surreptitious, concealed.
Under coverture.
A covering.
A disguise.
A feather that covers the bases of flight feathers.
Area of thick undergrowth where animals hide.
A hiding place.
Done with, and marked by, artful and dexterous secrecy; subtle
Light or delicate; slight; thin.
Artfully cunning; secretly mischievous; wily.
Dexterous in performing an action, so as to escape notice
Slyly.