a person that is EXTREMELY..... ugly. like beyond the point were you cannt look at them for one second or else you will puke. a trench face must walk in public wearing a thick black unsee-through bag over their face at all times. they can not take it off for any reason what so ever.
its would be like having trench foot, a disease during world war 2 caused by a person having their foot in muddy water for months and the cells in the foot die. and has black spots all over with blood leaking out. also the skin around the infected area is rotton, or is pealing off. due to the dead cells in the foot.