Related Clues:

• Like a recently robbed vault's door, say
• A pint? Not quite open
• Article definitely in German, third from Merkel not being totally open
• Partially open a beer
• Like a door when it's not a door, in a riddle
• A pot slightly open
• Not entirely shut
• Letting in air, as a door
• Open dry superior wine after common one
• A pot is slightly open
• A container that’s slightly open
• A container door could be this
• Letting in a draft, maybe
• Rues dunce somehow becoming loose
• Letting in light, as a door