Family relations by marriage: in-laws and step relatives
Spanish cuñado comes from Latin cōgnātus, which originally meant ‘blood relative’, that is, ‘sprung from the same stock, related by blood, kindred’ (L&S), as the meaning of its parts indicate: cō‑ (a variant of con‑ before some consonants) ‘together’ + gnātus (later natus) ‘born’, the passive participle of the verb gnāscī (later nāscī) ‘to be born’. It seems that the word may have been used in Late Latin to refer to any type of relative. In Old Spanish, cuñado/a referred to any non-blood relative, that is a relative by marriage (Sp. pariente por afinidad or pariente político), but by the 14th century it seems that the main meaning was the one it has today, namely ‘brother-in-law’ for cuñado and ‘sister-in-law’ for cuñada. Nebrija’s 1499 dictionary still gives ‘relative by marriage’ as one of this word’s meanings, a meaning that is today obsolete (DCEH).
Strictly speaking, the word cuñado/a is used to refer to the brother or sister of one’s spouse (Sp. hermano/a del cónyuge) or spouse of one’s brother or sister (Sp. cónyuge del hermano/de la hermana). In practice, however, the word cuñado/a is also used to refer to other extended relations, namely, for cuñado, wife’s brother-in-law or sister-in-law’s husband; and for cuñada, husband’s sister-in-law or brother-in-law. Note, however, that Spanish has a special word for these latter relationships, one derived from cuñado/a, namely concuñado/a, which is often shortened to concuño/a in Spanish America. This word is derived by means of the prefix con‑ ‘with’ added to the This term is more commonly used in some dialects of Spanish than others. Another term for cuñado/a is hermano/a político.
As we said, the word cuñado/a is patrimonial in Spanish since it descended uninterrupted by oral transmission from Latin and was not borrowed from that language later on as a learned word (Sp. cultismo). The form of the word cuñado is quite regularly derived from the Latin word cognatum/a, since Lat. gn always became ñ in Old Spanish, t became d between vowels, and o was often raised to u when next to a palatal consonant, such as in this case ñ (cf. Part I, Chapter 10).[a]