Non-huMan or NhM was the Imperial designation for aliens, humanoids, droids, cyborgs and female Humans. This label was a tool of Human High Culture, and it was said that NhM bigotry reached its height in the pre-Endor Imperial Navy.
Behind the scenes
When composing notes on the background of his universe for licensees in 1977, George Lucas suggested that female stormtroopers were not uncommon in the Empire, though few were stationed on the Death Star. They were probably located in other units. As such, the bias against females in the Empire as represented in the Expanded Universe appears to have not been a part of Lucas' intent. However, apart from several minor references, few female stormtroopers were referred to or appeared in licensed materials or the movies until the Star Wars: Legacy comic series.