Definition of pall:
(n) :
fine cloth, especially purple cloth used for robes; a
cloth used for various purposes on the
altar in a church
"1942: Thirty years or so later, a woman was put to death for stealing the purple pall from his sarcophagus, a strange, crazy crime -- Rebecca West, Black Lamb and Grey Falcon (Canongate 2006, p. 150)"
(v) :
to make
vapid or
insipid; to make lifeless or spiritless; to dull; to weaken