1681, from Romany (English Gypsy) pal "brother, comrade," variant of continental Romany pral, plal, phral, probably from Skt. bhrata "brother" (see brother).
"Better late than never, Pal, is a saying applicable on the present occasion." [Lord Byron, 1807]
The verb is first recorded 1879.
O.E. pæll "rich cloth, cloak, altar cloth," from L. pallium "cloak, covering," in Tertullian, the garment worn by Christians instead of the Roman toga; related to pallo "robe, cloak," palla "long upper garment of Roman women," perhaps from the root of pellis "skin." Notion of "cloth spread over a coffin" (c.1440) led to fig. sense of "dark, gloomy mood" (1742).
"become tiresome," 1700, from M.E. pallen "to become faint, fail in strength" (late 14c.), aphetic form of appallen "to dismay, fill with horror or disgust" (see appall).