'abruptly-missing' is a compound word formed from 'abruptly' and 'missing'. 'Abruptly' originates from Latin, specifically the word 'abruptus', where 'ab-' meant 'off' and 'rumpere' meant 'to break'. 'Missing' comes from Old English 'missan', meaning 'to fail to hit or find'.

'Abruptly' changed from the Latin word 'abruptus' and eventually became the modern English word 'abruptly'. 'Missing' evolved from the Old English 'missan' to the modern English 'missing'.

Initially, 'abruptly' meant 'broken off' and 'missing' meant 'not present'. Over time, 'abruptly-missing' evolved to mean 'suddenly absent'.