AbstractOnomatopoeia has not been paid much attention in theoretical linguistics, which may be related to its iconic‐symbolic nature. Moreover, the concept of onomatopoeia and its classification seem to vary in different linguistic traditions. Therefore, a new theoretical conception of onomatopoeia is proposed that makes it possible to examine onomatopoeia from a comparative perspective. This paper pursues the primary objective of clarifying the position of onomatopoeia in the system of language, in particular, whether or not onomatopoeia is an idiosyncratic group of words in the lexicon. This objective is implemented by evaluating the characteristics of onomatopoeia in English and Slovak from the semiotic and phonic points of view.