The paper deals with processing the entries describing colours in the Academic Dictionary of Contemporary Czech (ASSČ), the priority being the explanation of basic meanings of primary colours and lexicalised colour shades. The definitions ought to include all semantic features, be clear and should reflect the present world and the experience of the user. Special attention is given to the explanations of adverbs and compound adjectives. The paper also follows the decision-making process leading to the list of entries within a given category, based on the frequency of the lemma in the SYN corpus, and discusses the problem of appropriate exemplification.