question mark ˈquestion mark noun [countable]
a question mark over if there is a question mark over something, there is a possibility that it will not be successful or will not continue to exist:
• There is a big question mark over the bank's long-term future.
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question mark UK US noun
► [C, usually singular] a feeling of doubt about something: a question mark over/about sth »
There is a big question mark over people's willingness to invest in this scheme.
»The biggest question mark hanging over China's exports lies in the currency exchange rate.
► [C] MARKETING a product or company that has a small share of a market that is growing very fast: »
If nothing is done to change the market share, question marks will just absorb large amounts of cash.
Financial and business terms. 2012.