'sporadically-kept' originates from the combination of 'sporadic' and 'kept', where 'sporadic' comes from the Greek word 'sporadikos', meaning 'scattered'.

'sporadic' changed from the Greek word 'sporadikos' to the modern English word 'sporadic', and 'kept' is the past participle of 'keep', which has Old English origins.

Initially, 'sporadic' meant 'scattered or dispersed', and 'kept' meant 'maintained'. Together, they evolved to mean 'maintained irregularly'.