Evolution on the Lexical Workbench: Disentangling Frequency, Centrality, and Polysemy in Language Evolution

How do words evolve in their usage and meaning over time? We investigate the relationship between word frequency, semantic richness, and network centrality through longitudinal analysis of the Corpus of Historical American English (1820–2019). Using measures of semantic richness and network position, we find that a word's betweenness centrality—its tendency to bridge different semantic domains—consistently predicts both its future semantic richness and frequency of use. This relationship strengthens over longer time intervals, with the strongest effects observed across a 100-year span. Notably, while frequency and semantic richness are correlated as established in the literature, our results indicate that there was no directional relationship between frequency and semantic richness, while network centrality exerts a significant influence on both of these factors. Our results suggest that a word's position within the semantic network might play a crucial role in its evolution: words that bridge different semantic domains are more likely to develop new meanings and change in frequency over time. These findings offer new insights into the mechanisms driving language change.