Tarpaper is a 8 letter English word. It's valid Scrabble word worth 12 points. It's valid Words with friends word worth 14 points.
You can make 150 anagrams from letters in tarpaper (aaepprrt).
An Americanism dating back to 1890-95; tar1 + paper
Outside, the rain fell in great silvery sheets, so that the noise on the tarpaper roof of the barracks was almost deafening.
The roof will be of two thicknesses of boards, bent to a gentle oval over a stout ridge-pole, and again with tarpaper between.
The walls will be of shiplap, covered with matched siding, with tarpaper between.