language:enskos:prefLabel, skos:altLabel and skos:hiddenLabel are pairwise disjoint properties.language:enThe range of skos:altLabel is the class of RDF plain literals.
language:enAcronyms, abbreviations, spelling variants, and irregular plural/singular forms may be included among the alternative labels for a concept. Mis-spelled terms are normally included as hidden labels (see skos:hiddenLabel).