If you look at the definition in the dictionary it states: having qualities traditionally ascribed to men, as strength and boldness.
I do not agree with this just as I do not agree with the fact that people say that only women can be "feminine" . I am firm believer that people are born the way they are. My mom may have dressed my in dress and wanted me to be "feminine" but in side I wanted to play with the boys and wrestle play baseball. I could be referred to as masculine for the things I do and the way I look but I am not a man My boob's and vagina remind me everyday.