petticoat

Concise Oxford English Dictionary © 2008 Oxford University Press:
petticoat/ˈpetɪkəʊt/

▶noun

• 1 a woman's light, loose undergarment in the form of a skirt or dress.

• 2 [as modifier] informal, often derogatory associated with women: petticoat government.

– derivatives
petticoated adjective.

– origin ME: from petty coat, lit. ‘small coat’: the word orig. referred to a garment worn by men under a coat or doublet.