/ ˈfɪtnəs; NAmE / noun [ U ]
1.
the state of being physically healthy and strong :
a magazine on health and fitness
a fitness instructor / class / test
a high level of physical fitness
2.
fitness for sth / to do sth the state of being suitable or good enough for sth :
He convinced us of his fitness for the task.
There were doubts about her fitness to hold office.