Hermaphrodite

In biology, a hermaphrodite was an organism that had reproductive organs normally associated with both male and female sexes.

Despite their female-like voices, Alpha Centaurans were hermaphrodites and properly referred to as "it". Nevertheless, the Doctor generally used the masculine to refer to the Federation ambassador to Peladon. (DW: The Monster of Peladon)

Chelonians were hermaphrodites and all members could lay eggs. Despite this, Chelonians were referred to as males. (MA: The Crystal Bucephalus)

The Sloathes (NA: Sky Pirates!) and the Brascans (EDA: Kursaal) were also hermaphrodites.

There seemed to be no visual distinction between male or female Ood, which might suggest that they were hermaphrodites, however, when Donna called an Ood "it", the Tenth Doctor corrected her, saying she should call him a "he". (DW: Planet of the Ood)