B.
- Basal Body Temperature - One's body temperature in the morning before rising or moving about or eating anything. Some people use this to track ovulation, as a fertility awareness method.
- Bigender - A person whose sense of personal identity encompasses two genders.
- Binder - A garment used mainly by trans-masculine people to compress their breasts to give the appearance of having a flat chest.
- Binarism - The erasing or antagonizing of people whose genders are outside of the gender binary in indigenous and colonized cultures.
- Bioidentical Hormone - Substances with the identical chemical structure of natural hormones produced by the body. These are produced in a lab.
- Biological Sex - A medical term referring to one's personal combination of gonads, chromosomes, external organs, secondary sex characteristics and hormonal balances. Typically, this is used to refer to that what which one is born with, however several of these traits can be changed through the usage of hormones, and undergoing surgery.
- Bottom Surgery - A broad term referring to surgeries relating to genitalia.
- Boy Mode - Appearing to the world as a boy or man, regardless of one's true gender.
- Bra - A bra is an undergarment that is worn for the purpose of securing, enhancing, and embracing a set of breasts.
- Breast Augmentation - Cosmetic procedure to increase the size of breasts, typically with silicone or saline implants.
- Breast Forms - Artificial breasts, mainly used by trans-feminine people, to give the appearance of having breasts.
- Breasts - Either of two milk-secreting, glandular organs on the chest.
- Butch - Having an appearance or other qualities of a type traditionally seen as masculine.
- Butchphobia - The dislike or hatred of butch women.
