If you describe a girl's or woman's behaviour as unwomanly, you are critical of the fact that they are behaving in a way that you think is inappropriate for a woman.
[disapproval]
Society contrived to terrorise women with the threat that certain behaviour is unnaturaland unwomanly.
unwomanly in British English
(ʌnˈwʊmənlɪ)
adjective
1.
not possessing qualities, such as warmth, attractiveness, etc, generally regarded as typical of a woman