Why do both birds and planes have wings

Nearly 2,000 languages around the world follow common patterns for reusing words

02/07/2026

The study, led by UPF and published in Nature Human Behaviour, shows that languages around the world tend towards lexical economy when reusing words for different concepts does not cause communicative confusion.

In Catalan, we reuse words such as llengua (“language” or “tongue”), as well as word roots such as cuina (“kitchen”), cuiner (“cook”) and cuinar (“to cook”). The same occurs in nearly 2,000 languages worldwide as a result of linguistic and cognitive economy.

An international study led by UPF has determined that nearly 2,000 languages around the world follow common patterns to save or reuse words – or parts of words – when referring to different concepts. The study includes languages as diverse as English, Mandarin Chinese, Russian, German, French, Quechua and Swahili, as well as Catalan, Spanish and Basque. In all instances, the same universal principles apply, connecting linguistics to human psychology: the need to strike a balance between linguistic economy – and the mental effort required to learn a language – and communicative clarity.

Within this interplay between simplification and clarity, there is a tendency towards lexical economy whenever the use of similar words for different concepts does not generate confusion in the communicative context. Conversely, new words tend to be created when the reuse of existing ones causes confusion or ambiguity.

Such is the conclusion of the study recently published in Nature Human Behaviour and led by Thomas Brochhagen, a researcher in the Computational Linguistics and Linguistic Theory (COLT) group within the Department of Translation and Language Sciences at UPF. Co-authors include Xixian Liao (Barcelona Supercomputing Center - Centro Nacional de Supercomputación, BSC-CNS), Jamie D. Wright (now HERMES Programme (https://hermes-programme.eu/) at Vrije Universiteit Brussel-VUB and University of Namur) and Carmen Saldana (affiliated with UPF and the University of Barcelona).

Analysis of 1,995 languages from 193 different families

Using computational analysis methods, the researchers analysed the presence of common patterns in lexical economy processes across 1,995 languages from 193 different families. During the analysis, the researchers examined whether universal patterns exist in three different processes:

Full colexification: when the exact same word is used for two different concepts. Examples include llengua in Catalan (“language” or “tongue”), speak in English (“to articulate words” or “to know a language”) and shimi in Quechua (“mouth” or “word”).
Partial colexification: when words share a root or fragment, as with cuina (“kitchen”), cuiner (“cook”) and cuinar (“to cook”) in Catalan. Another example in English is the pair grandfather/grandmother, with both words using the prefix grand- to indicate a generational shift.
Differentiation: when different words are used, for example table and chair, to refer to two distinct concepts.

The analysis drew from the Lexibank repository, a large database of standardized lexical data for research purposes. Specifically, the analysis examined 25,138 instances of full colexification and 193,587 instances of partial colexification.

Previous studies had concentrated on shared patterns in full colexification across languages, without addressing partial colexification in depth, a research area that had remained unexplored until now. This study is pioneering in its analysis of partial colexification and shows that it also presents common patterns across languages, similar to those observed in full colexification.

Communicative context: a key factor in the reuse of words

In both cases, the analysis shows that languages are governed by a persistent tension between two opposing principles: lexical compression (reusing forms to facilitate learning) and lexical differentiation (avoiding ambiguity). The choice to use the same word depends on context: when two concepts commonly appear in the same scenarios (such as table and chair when talking about furniture), languages tend to differentiate them to avoid confusion. Conversely, if they are typically used in different contexts (such as bank as a financial institution and the bank of a river), ambiguity does not pose a problem and simplification tends to prevail.

According to Thomas Brochhagen (UPF): “When the use of the same word may generate ambiguity, speakers typically turn to a second option before resorting to one that is completely different. This option is partial colexification, since the use of a similar word will always be preferable, in terms of linguistic economy, to using a completely different term.”

Nonetheless, patterns of partial colexification are less homogeneous across languages than those of full colexification, which may be explained by the morphological or phonological differences between them. However, in general, both colexification processes are governed by the same universal principles of linguistic economy and communicative clarity.

Cited paper:

Brochhagen, T., Liao, X., Wright, J.D. et al. The interaction of meaning similarity and confusability explains regularity in form–meaning mappings at and below the word level. Nat Hum Behav (2026). https://doi.org/10.1038/s41562-026-02488-3

More information:

Jamie Wright +34 657 591 496