a freckled spot:

The word bohak, from the Syriac behak, to be white, or shining, here rendered "a freckled spot," is used by the Arabs to denote a kind of leprosy, of which Niebuhr says, "Bohak is neither contagious nor dangerous. A black boy at Mocha, who was affected with this eruption, had here and there upon his body white spots. We were told that the use of sulphur had relieved this boy for a time, but had not entirely removed the disease." He adds subsequently from Forskal's papers, "The Arabs call a sort of leprosy, in which some little spots shew themselves here and there on the body, behaq; and it is without doubt the same as is named bohak, ("And the LORDª spakeª° unto¹ Mosesª and Aaron,ª saying,ª° ... This¹ [is] the lawª of the plagueª of leprosyª in a garmentª of woollenª or¹ linen,ª either¹ in the warp,ª or¹ woof,ª or¹ any¹ thingª of skins,ª to pronounce it clean,ª° or¹ to pronounce it unclean.ª°" {Lev 13:1-59}). They believe it to be so far from contagious, that one may sleep with a person affected without danger.

"On the 15th day of May, 1765, I myself first saw the Bohak leprosy in a Jew at Mocha. The spots in this disease are of an unequal size. They do not shine; are not perceptibly higher than the skin; and do not change the colour of the hair. Their colour is an obscure white, inclining to red. The rest of the skin of the patient was darker than that of the people of the country in general; but the spots were not so white as the skin of an European, when not sun-burnt. The spots in this leprosy do not appear on the hands, or near the navel, but on the neck and face, yet not on that part where the hair grows thick. They gradually spread, and continue sometimes only about two months, but in some cases one or two years, and then disappear by degrees, of themselves. This disorder is neither contagious nor hereditary, nor does it occasion any inconvenience." Hence a person infected with the bohak is declared clean.