A petticoat or underskirt is an article of clothing for women; specifically an undergarment to be worn under a skirt or a dress. The petticoat is a separate garment hanging from the waist (unlike the chemise).
In historical contexts (sixteenth to mid-nineteenth centuries), petticoat refers to any separate skirt worn with a gown, bedgown, bodice or jacket; these petticoats are not strictly speaking underwear as they were made to be seen. In both historical and modern contexts, petticoat refers to skirt-like undergarments worn for warmth or to give the skirt or dress the desired fashionable shape. In this context a petticoat may be called a waist slip or underskirt (UK) or half slip (US), with petticoat restricted to extremely full garments. Petticoat can also refer to a full-length slip in the UK, although this usage is somewhat old-fashioned.
Petticoat is the standard name in English for any underskirt worn as part of non-Western clothing, most significantly, the lehenga with the sari.
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