This study was aimed at investigating the communicative implications of Nigerian
English usage. It explored, extensively, the peculiarities of this variety. The study employed normative research approach where in addition to the researchers’ participant discussions with various categories of Nigerian users of English, made an extensive impressionistic study of copious literature. Four research questions guided the study with a view to discovering the degree to which Nigerian English is a variant or a deviation. The inherent peculiarities discovered were sorted and classified according to the lexical, syntactic, phonological, semantic and slang variations. The result, therefore, revealed that with the degree of the deviations in all the linguistic levels, the majority of Nigerian English expressions constitute serious problems such that it requires further intensive analytical, linguistic investigation with a view to distinguishing standard from non standard forms. Based on this, the researcher went on to suggest that an in depth study be carried out on the features of the English of these categories of users and the result juxtaposed with those of competent users so as to establish a standard variety for the purposes of teaching and learning.