Ọ̀kọ is one of the many lesser described languages of Nigeria. Although it is structurally similar to some of its neighboring languages at the syntactic level (e.g. Yoruba), at the morphological level, there are several striking features which separate Ọ̀kọ from others. For example, the process of plural marking on some classes of nouns, the order of nouns and their modifiers, etc.
At the phonological level, several phonological processes are involved in the grammar of the language, such as vowel harmony, the phenomenon of nasal liaison, and more importantly grammatical tones. For example, tones are used to mark negation and are also employed for marking adpositions.