Constructing and exploiting different types of corpora are among computer applications exposed to the researchers in different branches of science including lexicography. In lexicography, different types of corpora may be of great help in finding the most appropriate uses of words and expressions by referring to numerous examples and citations. This article looks at some problems in lexicography that can be easily solved using monolingual and bilingual corpora. The main concern here is to show the advantages of monolingual target corpora as well as bilingual parallel corpora in finding the most precise and complete range of equivalents for dictionary entries. Here, it has been tried to compare the unstructured but complete information available in parallel corpora with the structured but incomplete information from the existing bilingual dictionaries. (Contains 4 figures.)