'unexpectedly-preserved' originates from the combination of 'unexpectedly' and 'preserved'. 'Unexpectedly' comes from 'unexpected', which is derived from the Latin 'ex-' meaning 'out of' and 'spectare' meaning 'to look'. 'Preserved' comes from the Latin 'prae-' meaning 'before' and 'servare' meaning 'to keep'.

'Unexpectedly' evolved from the Middle English 'unexpectid', while 'preserved' evolved from the Old French 'preserver'.

Initially, 'unexpectedly' meant 'not foreseen', and 'preserved' meant 'kept safe'. Over time, the combination has come to mean 'kept in a state that was not anticipated'.