To compose, arrange, or convert something into a ballad form; to create ballad poetry.
From 'ballad' plus the verb-forming suffix '-ise' (British spelling of '-ize'). The '-ise/-ize' suffix comes from Latin and Greek and means 'to cause to be' or 'to put into.'
British and American English still split on '-ise' vs. '-ize'—'balladise' is the British preference, showing how this verb usage is rare enough that most people never have to choose which spelling.
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