civilian clothing
civilian dress
civilian garb
plain clothes

The place was packed with men in civilian dress and uniforms of every description.

These "government passengers" were almost all Pakistani soldiers in civilian dress.

Men and women who, despite being in civilian dress, were obviously Mackensee officers.

By the next century, it would become widely adopted as civilian dress.

With them was a government man, a white soldier and an Asian woman in civilian dress who looked scared.

Kennecott turned and nodded to a woman in civilian dress, who left at once.

Several officers I didn't recognise were already there, along with other men and women in civilian dress.

A human in civilian dress appeared at the door of the tent.

Five men in civilian dress who looked like military types charged into the shop.