I broke in that dress at the wedding

[alpacinoutd]

Hello.

Does "break in" mean to use something for the first time? Or does it mean to use something for the first time to make it comfortable?

Have I used it correctly?

I broke in that dress at the wedding of my friend.
I broke in the shoes at a friend's party.

[emsr2d2]

In the case of shoes, it means wearing them a few times in order to make them feel less like stiff new shoes and, therefore, more comfortable. I've never heard of anyone breaking in a dress.

[alpacinoutd]

I see. Is there an idiom which means to use a dress for the first time?

[emsr2d2]

You could borrow from other contexts and say something like "I premiered my new dress at ..." or "My new dress debuted at ...".