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Brother (English) and bruder (German) are an example of words that are cognate.


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A cognate is a word that is related in origin to another word, such as English brother and German bruder, or English history and Spanish historia. Cognates have similar meanings and (usually) similar spellings in two different languages

"Cognates are often derived from Romance languages (French, Spanish, Italian) that have their origins in Latin, although some are derived from other language families (e.g., Germanic)," noted Patricia F.

Vadasy and J. Ron Nelson in their book "Vocabulary Instruction for Struggling Students" (Guilford Press, 2012).

If two words in the same language are derived from the same origin, they're called doublets; likewise, three are triplets.

Helping Learn Other Languages

Foreign language learners more easily acquire vocabulary in the new language if it's related to their native language. Author Annette M. B. de Groot illustrated the concept with an example that compares Swedish and Finnish learners of English:

"To illustrate, Ringbom (1987) reasoned that the existence of cognates might be one reason why Swedes are generally better in English than Finns; English and Swedish are related languages, sharing many cognates, whereas English and Finnish are completely unrelated. The consequence is that a Finn will be at a complete loss when encountering an unknown English word, whereas in many cases a Swede may infer at least part of the English cognate's meaning. It is plausible that explicitly pointing out to the foreign language learner that the native and targeted language share many cognates affects the way the learner approaches the vocabulary acquisition task, thus accelerating learning." ("Language and Cognition in Bilinguals and Multilinguals: An Introduction." Psychology Press, 2011)

Using cognates to teach vocabulary can be very helpful to English language learners (ELL), especially those students whose native language is Spanish: 

"Researchers indicate that English-Spanish cognates account for one-third of educated adult vocabulary (Nash, 1997) and 53.6 percent of English words are of Romance-language origin (Hammer, 1979). Cognates can provide a potent method of comprehending English vocabulary, but many Spanish-speaking students do not notice even the most transparent cognates they encounter in texts." (Shira Lubliner and Judith A. Scott, "Nourishing Vocabulary: Balancing Words and Learning." Corwin, 2008)

Not only can you learn new-language words faster and infer meaning to figure words out in context, but you can also remember the vocabulary more easily when the words are cognates. This kind of language study can begin with learners as early as preschool age.

Problems that come with learning vocabulary through cognates include pronunciation and false cognates. Two words might share similar spellings but be pronounced differently. For example, the word animal is spelled the same way in English and Spanish but pronounced with different stresses in each language.

False, Accidental, and Partial Cognates

False cognates are two words in different languages that appear to be cognates but actually are not (for example, the English advertisement and the French avertissement, which means "warning" or "caution"). They're also called false friends.

"False cognates are etymologically related but no longer overlap in meaning between the languages; their meanings may be related but also opposite (in English an auditorium is a place for a large gathering, whereas in Spanish an auditorio is an audience; stretch means 'to extend' in English but estretcher in Spanish is 'to make narrow'). Accidental cognates are not etymologically related but just happen to share form (English juice and Spanish juicio, 'judge'...)." (Annette M. B. De Groot, ​"Language and Cognition in Bilinguals and Multilinguals: An Introduction." Psychology Press, 2011)

Partial cognates are words that have the same meaning in some contexts but not others. "For example, twig and Zweig are used similarly in some contexts, but in other contexts Zweig is better translated as 'branch.' Both Zweig and branch have metaphoric meanings ('a branch of a business') which twig does not share." (Uta Priss and L. John Old, "Bilingual Word Association Networks" in "Conceptual Structures: Knowledge Architectures for Smart Applications," ed. by Uta Priss et al. Springer, 2007)