1. a woman's light, loose undergarment hanging from the shoulders or the waist, worn under a skirt or dress.
▪ used to denote female control of something regarded as more commonly dominated by men:"her play ends with a petticoat government coming to power"
Word Originlate Middle English: from petty coat, literally ‘small coat’: the word originally referred to a garment worn by men under a coat or doublet. The second sense derives from a later use to mean ‘skirt’.
Skirt-like undergarment, sometimes intended to show, worn under a skirt or dress
A petticoat or underskirt is an article of clothing, a type of undergarment worn under a skirt or a dress. Its precise meaning varies over centuries and between countries. Wikipedia