Linking the Dictionary of Medieval Latin in the Czech Lands to the LiLa Knowledge Base
Authors: Federica Gamba, Marco Carlo Passarotti, Paolo Ruffolo (Charles University Prague, Università Cattolica del Sacro Cuore, 2023)
Topic: Latin Resources

Abstract
The paper presents the process of linking the Dictionary of Medieval Latin in the Czech Lands to the LiLa Knowledge Base, which adopts the Linked Data paradigm to make linguistic resources for Latin interoperable. An overview of the Dictionary and of the architecture of the LiLa Knowledge Base is first provided; then, the stages of the process of linking the Dictionary to LiLa’s collection of lemmas are described. In conclusion, a query illustrates how interoperability allows for full exploitation of Latin resources.

Introduction
Latin benefits from a wealth of resources, making it one of the more privileged historical languages in terms of available linguistic data. However, the scattered nature of these resources across separate repositories hinders full access to the breadth of information they contain. To address this, the CIRCSE Research Center in Milan, Italy, launched the LiLa - Linking Latin project (2018-2023), with the aim of creating a Knowledge Base that enables interoperability among all Latin linguistic resources by adhering to the Linked Open Data (LOD) principles. These principles include using URIs for identification, making them accessible via HTTP, providing useful information upon lookup, and including links to other URIs for further discovery. The LiLa Knowledge Base already covers a broad range of interlinked resources, especially for Classical Latin. This is exemplified by the LASLA corpus, comprising 130 Classical Latin texts, and the Lewis and Short dictionary. The Knowledge Base also extends into later Latin stages, with resources like the Index Thomisticus Treebank, which includes works by Thomas Aquinas, the UDante treebank for Medieval Latin texts by Dante, and the Computational Historical Semantics Corpus, which covers canonical works like the Decretum Gratiani from the 12th century. Despite LiLa’s temporal breadth, it currently lacks spatial diversity, with no resources linked from Eastern European regions where Latin was historically used. To bridge this gap, the project sought to integrate the Dictionary of Medieval Latin in the Czech Lands, which compiles Latin vocabulary as used in the Czech region during the Middle Ages (1000-1500 CE). This dictionary, centered on a specific region and time period, presents valuable variability in both temporal and spatial dimensions, enhancing LiLa's lemma collection and its capacity for linguistic diversity. The paper is organized as follows: Section 2 introduces the architecture of the LiLa Knowledge Base, Section 3 provides details on the Dictionary, Section 4 explains the linking process between the Dictionary and LiLa, and Section 5 illustrates the benefits of interoperability in LiLa by presenting a sample query using the newly linked Dictionary data.

Conclusion
Linking the Dictionary of Medieval Latin in the Czech Lands to the LiLa Knowledge Base marks a significant step forward in maximizing the potential of linguistic resources for Latin by promoting their interoperability. This integration enhances the degree of linguistic diversity represented within LiLa, particularly in three key areas that are especially relevant to Latin, a language that spanned centuries across Europe: (a) diachronic diversity, as the Dictionary captures a portion of Latin vocabulary used during the Medieval period; (b) diatopic diversity, by incorporating Latin terms specific to the Czech lands; and (c) domain-based diversity, as the Dictionary frequently includes specialized terms from fields like flora and fauna. The inclusion of these lemmas substantially enriches the LiLa Lemma Bank, both in terms of the quantity and quality of entries, emphasizing the value of linking non-standard Latin varieties to the Knowledge Base. In the near future, further steps are planned to finalize the linking process. This will involve disambiguating ambiguous matches, adding missing lemmas to the Lemma Bank, and incorporating referencing lemmas in addition to full entries. Additionally, efforts will be made to model citations of attestations—references to other dictionaries and sources of example usages. The next phase of the project also aims to connect relevant documents from the same geographic region and time period as the Dictionary, such as those from the Czech Medieval sources in the AHISTO project. However, these documents are currently available only as raw texts and will require lemmatization before they can be integrated. Given the distinct nature of the local Latin variety, influenced by the Czech language and enriched with regional proper names, lemmatization using existing trained models is expected to yield low accuracy. This further highlights the importance of collecting non-standard Latin data and examining how different varieties of Latin may vary in their structure and use.