'unexpectedly-extended' originates from the combination of 'unexpectedly' and 'extended'. 'Unexpectedly' comes from 'unexpected', which is derived from Latin 'ex-' meaning 'out of' and 'pectare' meaning 'to look'. 'Extended' comes from Latin 'extendere', where 'ex-' meant 'out' and 'tendere' meant 'to stretch'.

'Unexpectedly' evolved from Middle English 'unexpectid', and 'extended' from Middle English 'extendid'.

Initially, 'unexpectedly' meant 'not expected', and 'extended' meant 'stretched out'. The combined form retains these meanings.