'often-built' is a compound word formed from 'often' and 'built'. 'Often' originates from Old English 'oft', meaning 'frequently', and 'built' is the past participle of 'build', which comes from Old English 'byldan', meaning 'to construct'.

'often' changed from Old English 'oft' to Middle English 'ofte', and eventually became the modern English word 'often'. 'Built' evolved from Old English 'byldan' to Middle English 'bilden', and eventually became the modern English word 'built'.

Initially, 'often' meant 'frequently', and 'built' meant 'constructed'. The compound 'often-built' retains these meanings, indicating something frequently constructed.