Toward the creation of W ord N ets for ancient I ndo- E uropean languages (2021)

Abstract: This paper presents the work in progress toward the creation of a family of WordNets for Sanskrit, Ancient Greek, and Latin. Building on previous attempts in the field, we elaborate these efforts bridging together WordNet relational semantics with theories of meaning from Cognitive Linguistics. We discuss some of the innovations we have introduced to the WordNet architecture, to better capture the polysemy of words, as well as Indo-European language family-specific features. We conclude the paper framing our work within the larger picture of resources available for ancient languages and showing that WordNet-backed search tools have the potential to re-define the kinds of questions that can be asked of ancient language corpora.

## introduction this paper presents the work in progress toward the creation of a family of wordnets for ancient indo-european (ie) languages, namely sanskrit (skt.), ancient greek (ag), and latin (lat.). this ongoing project is being jointly developed by an international team of scholars at the university of exeter, the university of pavia, the center for hellenic studies at harvard university, and the 1 the previous ancient greek and latin wordnets can be partly consulted here: http://www.languagelibrary.eu/new_ewnui/ . @xcite references to an ongoing project on the homeric lexicon, named homeric greek wordnet, which at the time, alpheios project, spearheaded by william m. short. the design, as well as the specific content, of these wordnets builds on several previous (but, as far as we know, now defunct) attempts in the field (for ag, @xcite @xcite , 1 extending and elaborating this work in certain critical respects (in particular, by bringing the framework under theories of meaning from cognitive linguistics). crucially, these wordnets share the same data organization and exploit of the same pool of sense designations (synsets), enabling comparison of linguisticabove all semanticstructures crosslinguistically through the use of a common set of definitional elements. in this paper, we discuss some of the innovations we have introduced to the wordnet architecture, to better capture the polysemy of words (including their figurative metaphorical and metonymic uses) as well as ie language family-specific features. we finally frame our family of wordnets in the wider picture of linguistic resources available for ancient languages. ## representing meaning in ancient language wordnets like previous wordnets @xcite , our ancient language wordnets are lexical databases in which meaning is stored in a relational way. wordnets comprise nodes for lemmas to which meanings are associated in the form of synsets, when the paper was published, was being developed at ilc, cnr, pisa. currently, the website https://cophilab.ilc.cnr.it/hgwnweb/ requires a username and password to be accessed, and detailed information on the status of the project does not seem to be available online. different lemmas can share one or more synset(s), which means that they are (partly) synonymous. other semantic relations are typically tagged in wordnets, which mostly interconnect synsets associated with lemmas of the same part of speech: for example, the hyponymy-hypernymy relation connects nouns to nouns (e.g. ag ikhthûs 'fish' and zôion 'animal'), the entails relation connects verbs to verbs (e.g. ag pléō (act) 'sail' and kinéomai (m/p) 'be in motion'), etc. (for similarities and differences between the traditional and our set of relations, see section 3.4). like in previous wordnets, our set of semantic relations fails to capture semantic solidarity due to belonging in the same frame @xcite or semantic field @xcite 10 tennis problem). thus, for example, no semantic relation links the ag words in (1): the sense in (2)a is the basic one, as salty morphologically derives from the noun salt. the sense in (2)b can be derived from (2)a via a metonymic process: a word denoting a state is employed to denote the physical sensation that such state triggers. the metaphoric meaning in (2)c can be connected with (2)a via the metonymic sense in (2)b: being salty is as positively or negatively engaging for the palate as being stimulating/provocative is for the spirit. the difference between cognitive metonymy and metaphor is that, with the former, the senses associated with the polysemous word belong to the same conceptual domain, whereas with the latter two senses belonging to different conceptual domains are mapped to one another. crucially, in our wordnets, we are implementing this principled view of polysemy by asking annotators to avoid multiplying the number of synsets associated to lemmas and to tag only senses that clearly do not emerge from context. moreover, our annotators are required to maximize the usage of the synsets deriving from the princeton wordnet for english, in order to enhance the compatibility of our wordnets with existing ones and to establish a common base of sense definitions. finally, while tagging senses of lemma entries, our annotators are asked to distinguish among synsets that correspond to literal, metonymic, and metaphoric meanings. for example, 16 synsets are currently associated to the ag word for 'salt', háls, and classified into three groups, viz. literal (4 synsets), metonymic (4 synsets) and metaphoric (8 synsets) senses, exemplified in (3)a, (3)b, and (3)c, respectively. as discussed above, the difference between metonymy and metaphor relies in being vs. notbeing part of the same conceptual domain. clearly, the senses of 'salt' and 'body of salty water' both pertain to the domain of sea; by contrast, the senses of 'salt' and 'wit' belong to two different domains (cf. the meanings of salty, remembered above in this section). as we are dealing with corpus languages that enjoy centuries of attestation and a long tradition of studies, each of the identified literal, metonymic, and metaphoric synsets will be tagged for its periodization(s), literary genre(s), and optionally loci, i.e., exemplifying attestations referred to by author(s) and work(s). thus, for example, the senses in (3)a-c are enriched with the following diachronic and stylistic metadata: we expect this information to be extremely useful for philologists, lexical typologists, and historical linguists interested in semantic change. on the one hand, as our wordnets will also include etymological information (section 3.1), users will be able to investigate whether skt., ag, and lat. cognate words lexicalize comparable arrays of concepts (see section 4). on the other hand, users will be able to track whether and how word meanings change over time and vary across literary genres and authors. ## integrating ancient language wordnets with existing resources the skt., ag, and lat. wordnets have been designed to be fully interoperable, as well as integrated into the larger ecosystem of digital lexical and textual resources for ancient languages. what is more, they make available a standard api (application programming interface) permitting any user, or computer application, to programmatically access their lexical and semantic content in a consistent manner, regardless of language (or simultaneously for all languages). for example, it would be trivial to discover the words in skt., ag, and lat. that correspond to the meaning 'a short stabbing weapon' (i.e., a dagger)represented by synset n#02542418simply by querying the endpoint /api/synsets/n/02542418/lemmas/ at the address of the relevant wordnet. more sophisticated queries could take advantage of the rich semantic, morphological, etymological, and figurative data that, while characterizing specific structures of a given language, are encoded through a set of language-independent (as it were, 'etic') elements. in fact, because they share certain linguistic structures (including etymological primitives) at a fundamental level, the sanskrit, greek and latin wordnets represents the first systematic attempt in classical language lexicography to deliver a basis for comparative semantic research (section 2). beyond interoperability, the architecture of the skt., ag and lat. wordnets aims to facilitate their integration with other lexical and textual resources. the lat. wordnet, for instance, is now being aligned with the erc-funded linking latin project ( https://lila-erc.eu ), which aims to standardize different resources around a single set of lemma-based uris. this will enable users to easily tie together information available from disparate lexical and textual resources by guaranteeing the correct identification of lemmas (e.g., in the case of ambiguous word forms). similarly, the sanskrit wordnet is tightly integrated with the digital corpus of sanskrit ( http://www.sanskritlinguistics.org/dcs/index.php ), which will allow users of this corpus to query semantic data utilizing pre-existing identification tags. the morphological encoding schema is compatible with the quasi-standard system used in most annotated corpora of greek and latin, adding two further fields to provide greater specificity in lexical categorization (see section 3.1). this is meant to enable scholars to inject semantic information, along with syntactic information, into natural language processing pipelines for the first time. at the same time, this means that other nlp tools already available for the ancient languages can automatically and immediately take advantage of the wordnet data to improve their functionality, accuracy, and scope. the sanskrit, greek and latin wordnets are, finally, designed to work hand-in-hand with electronic corpora of semantically annotated texts what we call "sembanks" on the model of syntactic "treebanks". the creation of the wordnets, on one hand, and of sembanks, on the other, in fact constitute two prongs of a single effort to bring research on ancient language semantics under computational approaches. for this reason, efforts are currently underway to produce a robust but flexible xml schema, following standards established by the text encoding initiative ( http://tei-c.org ) for use in annotating texts with wordnet constructs (above all, synsets) in order to capture the senses of words or larger textual units, as they occur in specific contexts. this schema incorporates the concept of a semtagm as a semantically meaningful unit consisting of one or more tokens and that of a reading, representing one discrete possible interpretation of the given semtagm. so, for example, the mark-up of the first sentence of the preface of cato's de agri cultura would consist of a sequence of semtagm elements, whose values correspond straightforwardly to definite synsets: @xmath0, 'have an existence, be extant'; @xmath1, 'on certain occasions'; @xmath2, 'value more highly'; @xmath3, 'the commercial exchange of goods and services' and so on. because the ancient language wordnets also include information about the figurative senses of words and the conceptual structures that underpin these senses (section 2), it is further possible to annotate the figurative senses of words. for example, in the following annotation of ovid's metamorphoses 13.11, the synset glossed "a hostile meeting of opposing military forces in the course of a war" (n#00610417) has been encoded as the contextual sense of mars, which is indicated as a metonymical usage of the god's name and includes a designation of the conceptual metonymy that motivates this interpretation: <semtagm @xmath4:phi0959.phi006.perseus-lat1" @xmath5.11:11:7"> <token @xmath6, moreover, to help capture the polysemy that tends to characterize word usage in literary contextsdue to textual problems arising from the process of transmission, intentional or unintentional lexical ambiguities, or genuine disagreements of interpretation in critical analysisby permitting annotators to tag lexical or phrasal tokens with multiple sense designations. thus, for example, the famous ambiguity of catullus's pudicitiam matris indicet ore, where os can be interpreted either as 'face' or (more specifically) as 'mouth' and again by metonymy, "speech", is represented by two reading elements within a single semtagm, to simultaneously encode synsets n#03683012, 'outward or visible aspect of a person or thing' and n#05319899, 'communication by word of mouth' as this word's possible interpretations. when combined with a next-generation corpus search tool like cylleneus, 4 wordnet-based semantically annotated texts will enable users to query ancient texts on the basis not only of their morphological and syntactic properties, but also of their semantic propertiesthat is, on the basis of the meanings of words as well as of the kinds of grammatical constructions in which they appear. for example, someone interested in ancient "courage" would easily be able to find occurrences of this concept in sanskrit, greek, or latin literature, simply by searching for a specific synset or some higher-order semantic category (semfield)without needing to conduct separate searches for each lemma. this would make identifying semantic intertextualities, for instance the ways in which one text creates new meanings by reworking the themes and ideas (not merely the verbal elements) of other textsalmost trivial. more generally, whereas current corpus search methodologies require painstaking and time-consuming "brute force" searching in order to identify patterns of usage, by abstracting away from the lexicon and thus permitting efficient queries of whole semantic fields (in conjunction with morphosyntactic queries), wordnet-backed search tools have the potential to redefine the kinds of questions that can be asked of ancient language corpora.