The noun adult is a common gender noun, a word for a male or a female.
Since a bull is referring to an adult or mature intact male, then, since the opposite of a male is female, the opposite of a bull would be a cow, which is an adult or mature female bovine that has had at least one or two calves.
Doctor is a neuter gender
Opposite gender of Filipino: Filipina
Some people use "duck" specifically for adult females and "drake" for adult males, others use "hen" and "drake", respectively.
Clot is not gender specific.
Opposite gender of a Filipino: FILIPINA
There isn't an opposite gender of farmer. A farmer can be either a male or a female.
An emperor is the opposite in gender to an empress.
The opposite gender of giantess is giant.
The opposite gender for Joseph is Josephine.
The opposite of dairymaid is dairyman.
gentlewoman....