'swiftly-grown' is a compound word formed from 'swiftly' (from 'swift' + '-ly') and 'grown' (past participle of 'grow'). 'Swift' originates from Old English 'swift', meaning 'moving quickly', and 'grow' from Old English 'grōwan', meaning 'to increase, flourish'.

'Swiftly-grown' is a modern English compound, combining the adverb 'swiftly' and the past participle 'grown' to describe something that has grown quickly.

Initially, the components meant 'to grow quickly', and the compound now describes something that has developed or increased in size rapidly.