'attach' originates from Old French, specifically the word 'atachier', where the prefix 'a-' meant 'to' and the root 'tachier' meant 'to fasten or fix.'

'attach' changed from Old French 'atachier' into Middle English forms such as 'attachen' and eventually became the modern English word 'attach'.

Initially, it meant 'to fasten or bind', but over time it broadened to include 'to affix, to add (e.g., a file), or to ascribe/attribute'.