underwear [2]
Garments worn next to the skin and under other garments.
boxer shorts 
Undergarment covering the tops of the thighs and held in place by an elasticized waistband.
union suit 
Warm undergarment that buttons up the front and combines a long-sleeved undershirt and long drawers.
athletic shirt 
Sleeveless tight-fitting undergarment with a very wide neck and armholes.
armhole 
Opening in a garment for the arm or for fitting a sleeve into.
neckhole 
Somewhat low part of the garment that goes around the neck.