The article shows semantic changes that took place among a group of lexemes connected with the notion ILLNESS and it shows the method by which the notion is conceptualized. There are a few highlighted domains in the notion of ILLNESS in the Polish language of the 16th century, some of them are (PAIN), (CRY), (WEAKNESS), (THINNESS), (DEATH). Some metaphors are based on this notion: ILLNESS is a CONTAINER, ILLNESS is a CAPTIVITY, ILLNESS is a SIN, ILLNESS is a PUNISHMENT. In the further material ILLNESS gets a new shape, it is perceived as a SWEARWORD.