civilian clothing
civilian dress
civilian garb
plain clothes

He had groused so long about my civilian garb that I finally gave in.

The young man there, dressed in civilian garb rather than a uniform, looked up at Frank's approach.

'They now wear civilian garb,' he said, and described what the five were wearing.

Men appeared from every corner of the docks, some in uniform, others in civilian garb.

Although attired in civilian garb, he had the bearing of a naval officer.

Half the men in town wore a mixture of military and civilian garb.

The other part of the year, he would dress in civilian garb.

Several men and women in civilian garb stood together behind him.

The mixture of dress uniforms and still-more-splendid civilian garb had almost reached him.

"That's right," said a man with a thick, dark mustache, also dressed in civilian garb.