Examples from the Web for underskirt
I made patches all over my underskirt except where I do sit down.
Now the mamma makes me raise up my dress when I come into the house so she can get a good look at my underskirt all around.
In deference to his inborn dislike, Dallas was wearing an underskirt of blue.The Plow-Woman|Eleanor Gates
By and by that flour-sack is going to evolute into an underskirt for me to wear under my dress when I go to school.
Louise was given two dresses a year; her old dress from last year, she wore as an underskirt.Slave Narratives: A Folk History of Slavery in the United States|Work Projects Administration