The word 'dud' is correct and usable in written English.
It is a slang term used to describe something that is a failure or is not effective. Example sentence: The new phone turned out to be a dud and the reception was terrible.
The late 20th-century model – of speeches, spin and central diktats – is a dud.
She has an unerring ability to see things from an objective point of view, and can spot a dud policy a mile off.
If you get a dud Tory or dud Labour member, it doesn't make you feel the whole party is incapable of producing a decent MP".
On the way, she had encountered dud radios, severe icing-up, defective brakes and a malfunctioning engine.
Authors, publishers and literary critics struggling to unlock the secrets of successful writing can breathe a sigh of relief, after a computer science professor has announced an algorithm that can tell the difference between a dud and a literary hit.
The money will allow for a clean-up of bank balance sheets begrimed by dud loans granted to property developers during the inflation of Spain's colossal property bubble.
If a bank reports a dud loan, the RBI will assemble the firm's lenders to agree on remedial action.
These reductions will be in addition to the loss of tens of thousands of other temporary jobs created to process dud mortgages.Some of the cuts are long overdue.
It will take dud loans from those being restructured.
Pessimists can point to the experience of big banks such as Citigroup, that are still trying to offload huge portfolios of dud assets almost a decade after the crisis.
No doubt plenty of venture capital will be squandered on dud fintech companies.
