petticoat [LME] This comes from the phrase petty coat which means literally ‘small coat’. It was originally a masculine garment, a tight-fitting undercoat worn underneath a doublet or a padded jacket to go under armour. It seems to have been used for a similar under-garment for women. In the late 15th century it started to be fashionable for women to wear full skirts open down the front in an inverted V-shape, the gap filled with a contrasting underskirt, and the term petticoat was transferred to this under-garment.