Metathesis, the transposition of letters and syllables, is a minor phonological process that is found in both English and Tiv languages. This phonological process has not received much attention it deserves because most scholars considered it as a figure of misspelling which is not worthy of researching. This paper investigates the nature of English and Tiv metatheses. The objectives of this paper are to classify English and Tiv metatheses, discuss the formation of metatheses in English and Tiv and state the functions of metatheses in English and Tiv languages. This paper used comparative linguistic theory which compares the nature of English and Tiv metatheses. The researcher used participant observation tool for elicitation of data for this study. Secondary materials such as journal articles, textbooks, dictionaries and encyclopaedias and Internet sources were used. This study links phonology, historical linguistics, onomastics and language pathology (speech disorder). The study has established that metathesis has phonological, orthographic, metrical and onomastic relevance. This paper provides an in-depth material for teaching and learning of English and Tiv languages. It has been recommended that lecturers in the National Institute for Nigerian Languages, Departments of Linguistics and Nigerian Languages should write books and critical works on Nigerian or African languages.