One of the main functions of a dictionary is to give the definition of meanings of various words. This view is supported by various writers who have attempted to explain the meaning of a dictionary. Sally (2005) for instance, views a dictionary as a book that gives a list of words of a language in alphabetical order and explains what they mean or gives a word for them in a foreign language. This paper therefore, seeks to have a critical assessment on the way this function is implemented and wonders whether the goal is fully attained or not. The paper focuses on examining the definition of meaning of various words in dictionaries based on the Oxford Advanced Learner’s Dictionary (OALD), 7th edition. The strengths and weaknesses of word meanings in dictionaries form the base of this study. The paper concludes that, despite the weaknesses that OALD demonstrates in defining the meanings of various words, this dictionary seems to have more strengths than weaknesses, something which gives hope that dictionaries have to a good extent attained the goals for their existence.