MorfFlex: Handling Rich Morphology
For linguists and NLP researchers working on morphologically rich languages, MorfFlex provides a scalable and consistent morphological resource, though it is an incremental contribution building on existing dictionary and annotation practices.
MorfFlex is a morphological dictionary architecture for languages with rich inflection and derivation, exemplified by MorfFlex CZ for Czech, which encodes patterns to reduce dictionary size while covering over 100 million wordforms and 1 million lemmas. It ensures annotation consistency in the Prague Dependency Treebanks and supports state-of-the-art tools like MorphoDiTa.
We present MorfFlex, a morphological dictionary architecture suitable for languages with extensive regularity in both inflection and derivation. As the primary example of MorfFlex in use we introduce MorfFlex CZ, a morphological dictionary of Czech. It is distributed as a simple, unstructured list of <wordform, lemma, tag> triplets, however, its manually maintained, unpublished source files and conversion scripts encode a sophisticated system of inflectional and derivational patterns. These patterns dramatically reduce the otherwise enormous size of the dictionary, which currently contains over 100 million wordforms and more than 1 million lemmas. The MorfFlex CZ dictionary serves as an essential resource for ensuring the consistency of manual morphological annotation in the Prague Dependency Treebanks and underpins state-of-the-art automatic tools such as MorphoDiTa. In this paper, we focus on: (i) presenting an effective method for managing the rich morphological system within the dictionary, and (ii) demonstrating the utility of such a language resource for maintaining annotation consistency in corpora and supporting the development of advanced NLP applications.