The present study examines the role of word classes in contemporary lexicography using examples from Estonian. Since Estonian is a morphologically rich language, the results may be extendable to other languages with abundant morphology. Two research questions are examined: i) What are the problems and practices of lexicographers when determining word classes? and ii) What are the needs and expectations of lexicographers for a possible digital tool that would facilitate word class identification? The results of a metalexicographic survey carried out among 23 Estonian lexicographers show the relevance of word classes as a categorial frame in their lexicographic work. There is a need to improve or reconsider the (theoretical and technical) factors influencing the process of PoS tagging. A reliable software application (provisionally a PoS evaluator) easing the decision making process would be welcome. According to the ideas suggested by the respondents, the solution would be an improved morphological and syntactic parsing system with respect to the present solutions, and a corpus-driven application presenting statistics with regard to the morphosyntactic distribution of an ambiguous word with access to the data source.