What is Uncertain ?
Uncertain is adj 1. not sure She is uncertain as to whether her father will come to stay. Their plans are still uncer- tain. He’s uncertain about what to do next. 2. in no uncertain terms rudely He told him in no uncertain terms what he could do with his offer. 3. which will probably change for the worse She faces an uncertain future.
source: Easier English, Student Dictionary Upper Intermediate Level