'relink' originates from a combination: the prefix 're-' which originates from Latin, specifically the element 're-' where 're-' meant 'again', and 'link' which originates from Old English/Middle English, specifically the words 'hlenc'/'linke' where they meant 'a connection' or 'ring'.

'relink' was formed in modern English by attaching the prefix 're-' to the existing word 'link' (Middle English 'linke', Old English forms), producing the verb meaning 'to link again'.

Initially, 'link' meant 'a connection' (and the verb 'to link' meant 'to make a connection'); combining it with 're-' produced 'relink', which came to mean specifically 'to make that connection again' (to link again).