Giant can be used for both genders. Giantess can be used for a female giant, but using giant is acceptable.
The opposite gender of giantess is giant.
Sorry, 'giant' does not denote or connote gender at all.
The 8-letter "opposite gender" of a male giant is "giantess." (There is no common 8-letter antonym to a giant or to the adjective giant.)
Doctor is a neuter gender
Clot is not gender specific.
The opposite gender of fraternity is sorority.
An emperor is the opposite in gender to an empress.
Opposite gender of Filipino: Filipina
The opposite gender to "negro" is "negra" in Spanish, which translates to "black" and "black woman" respectively.
The opposite gender is girl.
The opposite of dairymaid is dairyman.
Parrot