For me, 'feminine' mainly refers to the neutral gender designation or, more loaded, to adult femininity.
'Girly' really refers to immature feminine, so really girlish in appearance (clothing, hairstyle) and/or in behavior (giggles, etc.), but also precisely the really charming aspects of girls.
Incidentally, the photos on your profile, KimberleyAnne, are a very nice crossover between feminine and girly, where the clothing is mainly the first and your personal appearance the second; but then especially the charming aspects of the girl.
in my vernacular, they are very similar. I use 'girly' when playfully referring to the 'cuter' feminine qualities (e.g., a woman wears make-up or cute clothes to be a girly girl ;)
in your photos, all of your outfits are feminine, the pink dress is more 'girly'
I think of feminine as being pretty much the classic/stereotypical definition of a woman -- less harsh than masculine, more graceful, more caring, more empathetic, etc. "Girly" I think of as being characterized by giddiness, immaturity, and an exaggerated version of a teen female.
@SeekingConnection I don't think "girly" necessarily implies childishness or immaturity, it just implies the feminine style for girls below 17-18 circa. The style is not immature if it's age-appropriate (unless immature just means young, but you can be more or less mature relative to your age). 🌸
All girly things are feminine, but not all feminine things are girly. Basically feminine is a broader term for traits associated with women or girls, while girly refers to something that is typical of a girl or woman.
They mean different things to me. I know that I have some of the qualities of being feminine... but I struggle with being "girly" - to me, that means I find it difficult to express my feminine side outwardly in terms of my appearance.
The Cambridge Dictionary actually defines "Girly" as this, which is very similar to what I described:-
(of a person) enjoying things typically connected with women or girls, for example, make-up or the colour pink: Is your man more girly than you?
Not really. Both boy and girl have both masculine and feminine traits. Feminine means those related to the physic only like waist, hips, breasts etc. Whereas girly is more of external appearance that are clothes, accessories and so on which is culture.
Best way to think of it is the difference between feminine and effeminate.
The two are not the same. Feminine applies to females (including girls and women).
Effeminate applies to acting like yet not really feminine. Say male to female transvestites.
Even young girls use "feminine" products. That's actually apart of the labeling for such products.
Girly can apply to both girls and women. Though some might take exception. Yet flowers is considered "girly" by many "boys" for both girls and women. It's normally only used by young boys.
SW-User
I would say they a similar with some things that a different
id mostly think of girly as a subset of feminine. i can't think of much that id call girly that isnt feminine to some degree. a significant intersection, but not all the same