'accidentally-shown' originates from the combination of 'accidentally' and 'shown', where 'accidentally' comes from Latin 'accidentalis', meaning 'happening by chance', and 'shown' is the past participle of 'show', from Old English 'sceawian', meaning 'to look at'.

'accidentally' evolved from the Latin 'accidentalis' through Old French 'accidental', and 'shown' evolved from Old English 'sceawian' to the modern English 'show'.

Initially, 'accidentally' meant 'happening by chance', and 'shown' meant 'to look at'. Over time, 'accidentally-shown' evolved to mean 'revealed unintentionally'.