Sentence:  The <WSD>minimal polynomials</WSD> of the images of unipotent elements in irreducible rational representations of the classical algebraic groups over fields of odd characteristic are found....It occurs that for each unipotent element the degree of its <WSD>minimal polynomial</WSD> in an irreducible representation is equal to the order of this element provided the highest weight of this element is large enough with respect to the ground field characteristic. 
Meaning of the word marked with <WSD> tags:  Given an algebraic element "α" of a given extension field of some field "K", the monic polynomial of smallest degree of which "α" is a root.