'unimaginatively-kept' is a compound word formed from 'unimaginative' and 'kept'. 'Unimaginative' originates from the prefix 'un-' meaning 'not' and 'imaginative', which comes from Latin 'imaginativus', meaning 'able to imagine'. 'Kept' is the past participle of 'keep', from Old English 'cēpan', meaning 'to seize, hold'.

'Unimaginative' evolved from Middle English 'imaginatif', and 'kept' from Old English 'cēpan'. The compound form 'unimaginatively-kept' is a modern English creation.

Initially, 'unimaginative' meant 'lacking in imagination', and 'kept' meant 'maintained'. Together, they describe something maintained without creativity.