This article attempts to the present the most important results of an analysis of Polish and Russian exponents of adnumerative approximation (e.g. Pol. 'okolo', 'przeszlo'; Rus. 'primerno', 'bolee', etc.). Approximation is defined here as a mechanism of numeric attribution, based on designating a segment in a series of numbers, instead of designating one particular point. This definition encompasses several different ways to designate a segment. All of those ways have separate exponents in Polish and Russian. Analysis indicates that exponents of the same sense can differ in terms of connectivity, semantics and stylistics. These differences should be taken into consideration while establishing Polish and Russian translational equivalents.