In this paper we present a quantitative analysis of a bilingual lexical database which has been produced with OMBI, a tool for creating and editing bilingual dictionaries. OMBI has proven to be a valuable tool in the creation of rich bilingual multi-purpose lexical databases. One of the most distinctive features of the tool is reversal of source language and target language in order to create bilingual dictionaries in an economic and accurate way. We will focus on OMBI's reversal function, its initial concept and its results in practice. © 2007 Oxford University Press. All rights reserved.