a question mark hang over something
US /ə ˈkwes.tʃən mɑːrk hæŋ ˈoʊ.vər ˈsʌm.θɪŋ/
UK /ə ˈkwes.tʃən mɑːrk hæŋ ˈoʊ.vər ˈsʌm.θɪŋ/
1.
a feeling of doubt or uncertainty about something
:
•
A question mark hangs over the future of the company.
•
His involvement in the scandal still has a question mark hanging over it.