toss-up
/ˈtɒsʌp/noun
1- informal the tossing of a coin to make a decision between two alternatives〈非正式〉掷硬币决定两者之间的取舍。
1.1
- a situation in which any of two or more outcomes or options is equally possible or equally attractive相等机会; 难以定夺的事：
the choice of restaurant was a toss-up between Indian or Chinese.
选择餐馆时, 印度餐馆和中国餐馆都很有可能。