If a return value is not otherwise specified, the default return value for a function is int.

如果返回值没有指定，那么函数的缺省返回值是int类型的。

youdao

Instead of using the current terms of autistic disorder, Asperger's disorder, childhood disintegrative disorder and PDD-NOS (pervasive developmental disorder not otherwise specified), people will be given an umbrella diagnosis of "autism spectrum disorder".

BBC: Children 'may grow out of autism'

Most people think of eating disorders as either anorexia or bulimia (self-induced purging), but there is a less recognized clinical syndrome, disordered eating not otherwise specified, which may affect a significant portion of the population and seems to be especially prevalent in female college athletes.

CNN: Why do I always think about food?