From Latin 'catena' (fetter) via Old French — replaced native Old English 'racente' and gave us 'concatenate.'
A series of connected metal links or rings used for fastening, securing, pulling, or as an ornament; by extension, any connected series.
From Middle English 'chaine,' borrowed from Old French 'chaeine' (Modern French 'chaîne'), from Latin 'catēna' meaning 'chain, fetter, restraint.' The Latin word has no certain PIE etymology — it may be borrowed from an Etruscan or other Italic substrate language. Latin 'catēna' also produced 'concatenate' (to link together) and 'catenary' (the curve formed
German 'Kette' (chain) was also borrowed from Latin 'catēna,' not inherited from Proto-Germanic — meaning that across the Germanic languages, the native words for chain were systematically replaced by the Latin word, a testament to how thoroughly Roman material culture transformed Germanic vocabulary through trade and conquest.