Cognate

In historical linguistics, cognates are those terms that have the same etymological origin, but a different phonetic evolution and, often, also a different meaning.

For example, encyclopedia or encyclopaedia (from English) is a cognate of enciclopedia (in Spanish). Sometimes long series of cognate terms can be written within the same family of languages. For example, among the Indo-European languages there are these two series of cognates:

1. night (Spanish) night (English) nuit (French) Nacht (German) nacht (Dutch), nat (danese) noc (check, Polish and Slovak) Noch (Russian) noć (croata) noć (Serb) Nox (Latin) nakti- (signed) natë (Albanian) us. (Games) nueche (asturian) nueit (aragones), noite (Gallego and Portuguese) Notte (Italian) nit (catalan) nich (Ukraine) Noapte (ruman) No. (Iceland), νŭχτα Nijta (modern fire) and naktis (Lithuanian). They mean ‘night’ and have an obvious phonetic similarity; this is because they all derive from protoindoeuropeo ♪^wts ‘night’.
2. star (Spanish) star (English) Etoile (French) Stern (German) Stjerne (danese) ster (Dutch), stella (Latin, Italian) str (signed) seren (Games) Estrela (aragones), Estrela (Gallego and Portuguese) estel (catalan) stea (ruman) stjarna (Icelands), αστ astéri (modern fire), setare (persa) and estêre (kurdo). In this case, they all mean ‘star’ and derived from protoindoeuropeo *h2strr ‘star’.

The similarity of cognate words often leads to mistranslations, such as the English actually for "actually", although what it means is "really" or "in fact"; or as policy, which seems to mean "police", when it really means "rule". These terms are called false friends.

Etymology

The word «cognate» is derived from the Latin cognatus, from co- 'with', and -gnatus, natus , participle of the Latin verb nascor 'to be born'. Its literal translation would be 'blood, with the same ancestor', 'acquaintance' or 'related by the same nature, characteristic or similar function'.

Doublets

The lexical doublets are cases of two cognate words within the same language. In the Romance languages, cases in which one of the words is the result of successive transformations from Latin to Latin are common. centuries (patrimonial word, eg fire), while the other is a cultism reintroduced in more recent times (eg focus) when both come from from the same source: focus; or a linguistic loan that in turn comes from Latin, as in Spanish cadera and cátedra (both from Latin cathedra, but the first is a patrimonialism and the second a cultism),; finally, a borrowing from another language, as in work and opera (opera comes from the Latin opera through from Italian).

False cognates

The false cognates are those words that seem to have a common origin, but after a linguistic study it can be determined that they do not have any type of relationship. Thus, for example, based on superficial similarities, we might assume that the Latin verb habere and the German haben, meaning "to have", are cognates, but it is not. So. If we understand how both languages evolved from Proto-Indo-European roots, we see that they cannot be: haben actually comes from Proto-Indo-European *kap- "to grab", and its real cognate in Latin is capere "to take, capture". The Latin verb habere, on the other hand, derives from the Proto-Indo-European *gʰabʰ- "to give, to receive", so it is the cognate of the German verb geben "give". Similarly, compare the English words give and have with the Spanish haber and caber, derived from *gʰabʰ- and *kap- respectively.

The similarity between words of different languages is not enough to demonstrate that these words are related to each other, in the same way that only by a physical similarity it is not possible to determine if two people have the same genes. After thousands and thousands of years, words can change their pronunciation completely, making it difficult to identify them: for example, the word "cabeza", in English head and Spanish cabeza are both cognates derived from Proto-Indo-European *kapot, while English over and Hebrew a'var are not.