Evolution and Spread of Ideology-Related Keyword Usage Across Disciplines: The Surge and Dissemination of ‘Gender’ and ‘Green’

It remains unclear how different academic disciplines conceptually interpret the social world. This study analyzed 1,283,449 abstracts published between 2002 and 2024 across twelve disciplines: Sociology, History, the Humanities, Philosophy, Linguistics, Politics, Economics, Medicine, Biology, Chemistry, Physics, and Mathematics. Through a bibliometric analysis of 26,073 Sociology abstracts, this study identified 23 “top differentially frequent ideology-related keywords” (Top DIKs). Over the study period, ‘gender’ and ‘women’ rose to prominence, whereas keywords traditionally associated with macroscopic social structures or collective solidarity, such as ‘EU’ and ‘minority,’ exhibited a decline. The frequency of these gender-related keywords in Sociology increased linearly, eventually appearing in 7–9% of all publications. Notably, ‘gender’ showed one of the highest rates of increase among all analyzed terms, transcending its specific classification as an ideology-related term. Other disciplines followed this upward trend starting in the early 2010s, albeit with lower absolute frequencies (reaching 1–4% in the human sciences and 0.2–2% in the natural and mathematical sciences). Furthermore, across all twelve disciplines, ‘women’ appeared approximately twice as frequently as ‘men,’ reflecting a persistent asymmetry in research focus. This trend was accompanied by relatively less academic attention to physical social risks compared to their real-world prevalence. Local context-level co-occurrence analysis categorized these disciplines into five distinct clusters, revealing shared conceptual vocabularies. Group 1 (Sociology and the Humanities), Group 2 (History, Philosophy, and Linguistics), and Group 3 (Politics and Economics) collectively formed a broad human sciences cluster, while Group 4 (Biology and Medicine) and Group 5 (Physics and Mathematics) aligned as the natural and mathematical sciences. Although Chemistry shared substantial similarities with Biology, its divergence from Medicine precluded the formation of a single cohesive cluster. This classification highlights a profound affinity between Sociology and the Humanities regarding their ideology-related vocabularies. This connection is further supported by the contextual diversity of gender-related keywords: for instance, while Medicine and Chemistry emphasized women’s healthcare and reproduction, Sociology focused on women’s rights. In contrast to these trends, the usage of ‘green’ in Chemistry showed a linear increase throughout the study period, reaching 3.5% of publications. Meanwhile, the human sciences (Sociology, the Humanities, Economics, and Politics) exhibited rapid growth after 2019, nearly converging with the levels observed in Chemistry. Co-occurrence patterns revealed a notable semantic divergence between Chemistry and the human sciences. Regarding ‘green,’ Economics and the Humanities formed a tight cluster, contrasting with the patterns for ‘gender’ and ‘women,’ where Sociology and the Humanities were more closely aligned. Collectively, these findings offer a data-driven framework for understanding the evolution and dissemination of ideology-related keywords, underscoring the structural dominance of specific issues. These observations reflect a shift in thematic priorities, signaling a transformation in how academic disciplines engage with societal concerns. Moreover, the ubiquity of these terms masks divergent conceptual frameworks across disciplines, highlighting the necessity of contextualizing interpretations within interdisciplinary research. DOI: https://doi.org/10.5281/zenodo.18738068