Phrases Asking for Clarification

I'm not quite sure what you mean by…

Meaning

I'm uncertain about your meaning of…

Translation language

John: 'The deliverables are due next week.'
Alice: '<b>I'm not quite sure what you mean by</b> 'deliverables' in this instance.'
John: '<b>I'm not quite sure what you mean by</b> 'compliance' in this situation.'
Alice: 'The new policy requires compliance.'