'individually-kept' originates from the combination of 'individual' and 'kept', where 'individual' comes from Latin 'individuus' meaning 'indivisible', and 'kept' is the past participle of 'keep', from Old English 'cēpan'.

'individually-kept' combines the modern English word 'individual' with 'kept', forming a compound adjective.

Initially, 'individual' meant 'indivisible', but over time it evolved to mean 'separate or distinct', and 'kept' has maintained its meaning of 'maintained or preserved'.