The puff sleeve blouse. Always popular in almost every decade of the 20th century, particularly for young women. Judging from photographs I have seen, the simpler version (unlike the exaggerated sleeves of previous decades) was kind of de rigeur in the 40s (MS Subbulakshmi loved them if the photographs are any indication).
In the pics: Postcard of a Prabhu woman; MS Subbulakshmi; Aishwarya Rai; Nayantara; Unknown; Konkona Sen Sharma
“First of fair sex to obtain motorcycle license in Capital. Washington, D.C., Sept. 15. Although she weights only 88 pounds–one-third of the machine she rides, Mrs. Sally Halterman is the first woman to be granted a license to operate a motorcycle in the District of Columbia. She is 27 years old and 4 feet, 11 inches tall. Immediately after receiving her permit, Mrs. Halterman was initiated into the D.C. Motorcycle Club – the only girl ever to be accorded this honor.” Photo by Harris & Ewing, 1937 September 15. http://hdl.loc.gov/loc.pnp/hec.23371