'zealously-built' originates from the word 'zealous,' which comes from the Greek word 'zelos,' meaning 'ardor' or 'fervor.' The suffix '-ly' is used to form adverbs, and 'built' is the past participle of 'build,' which comes from Old English 'byldan,' meaning 'to construct.'

'zealous' changed from the Greek word 'zelos' to the Latin 'zelus,' and eventually became the modern English word 'zealous.' 'Build' evolved from Old English 'byldan' to the modern English 'build.'

Initially, 'zealous' meant 'ardor' or 'fervor,' but over time it evolved to mean 'enthusiastic or passionate.' 'Build' has largely retained its original meaning of 'to construct.'