We analyze lexical iconicity of basic aesthetic expression categories in Serbian language which expressed concept of ugly-ružno and grdno (“ugly“). Their iconicity is, first of all, associated with the imagination of earthly substance (grdan), but is formed in connection with divine-human-animal opposition (ružno). The lexeme ružno (<*ureng- “bend” which is also contained in režati „growl”, „snarl”) which has taken over semantic components of the lexeme grdno is, on the other hand, determined by an opposition of human-inhuman and its iconicity contains images of animal like, deviant behaviour unsuitable to a human. Concept of grdno (<*gьrdь <*gher- “abrade”, or *ghreu- “sharp”) is determined by an image of a substance which is uneven, rough and unsuitable for moulding. Esthetical and ethical categories in both former and later cognitive thinking are interconnected - evil and ugly oppose beautiful and good but they are also defined by them. [Projekat Ministarstva nauke Republike Srbije, br. 47016: Interdisciplinarno istraživanje kulturnog i jezičkog nasleđa Srbije. Izrada multimedijalnog internet-portala Pojmovnik srpske kulture]
