The Spanish word 'cadena' meaning 'chain' comes directly from the Latin word 'catena', which also meant 'chain'. During the evolution from Latin to Spanish, the medial 't' sound softened to a 'd', which is a common sound change pattern in Spanish words derived from Latin. This transformation from 't' to 'd' between vowels (lenition) is one of the characteristic features of Spanish's development from Latin.

The word 'cadena' is a fundamental Spanish word and is itself commonly used, appearing in many contexts like 'cadena de montañas' (mountain chain) and 'cadena perpetua' (life imprisonment). It has also given rise to related Spanish words like 'encadenar' (to chain) and 'cadeneta' (chain stitch).

While English 'chain' comes from a different source (Old French 'chaeine'), English has several words derived from the same Latin 'catena'. These include 'concatenate' (to link things together in a chain or series), 'concatenation' (a series of connected things), and the technical term 'catenary' (the curve that a chain or rope makes when hanging freely between two points). Understanding this connection can help English speakers remember that 'cadena' refers to a chain or sequence.