M.
- M.2.F. - Male "To" Female
- M.2.N. - Male "To" Neutral
- M.2.X. - Male "To" [Unspecified Gender]
- M.A.A.B. - Male-Assigned At Birth
- Macrogender - When one has large feelings of gender that are not identifiable within social gender categories.
- Male-Bodied - A common but problematic term used for cis men and AMAB trans people who have not undergone transitional surgery.
- Male Impersonator - A person who dresses or acts as male, but does not identify as male, often for the benefit of an audience.
- Malgender - To affirm someone's gender identity only to use it against them.
- Man - Someone who identifies as a man.
- Masculine of Center - Having a gender that is closer to “male” than to “female” or other genders.
- Masculinization -
- The process by which a person’s gender presentation becomes closer to what is traditionally considered masculine.
- In fetal development, the process by which male sex hormones affect the developing brain.
- Mastectomy - Removal of breasts.
- Maverique - A strong feeling of gender that is separate from that of being male, female, or neutral.
- Medical Tattooing - Tattoos which are used to cover up surgical scarring, or to otherwise make a body part to look more "normal."
- Medical Transition - When someone takes hormones (such as estrogen or testosterone) or undergoes surgery in the pursuit of gender euphoria.
- Menstrual Cup - A reusable product intended for collecting menstrual blood.
- Menstrual Disc - A reusable product intended for collecting menstrual blood.
- Metoidioplasty - A surgery that constructs or approximates a penis by enlarging and reshaping the clitoris. A type of FTM bottom surgery.
- M.H.T. - Masculinizing Hormone Therapy
- Microgender - When one has small feelings of gender that are not identifiable within social gender categories.
- Minoxidil - A substance used to stimulate hair growth.
- Mirdam - A gender neutral title that can be used in the same manner as words like sir or ma'am.
- Misgender -
- To refer to someone using the incorrect pronouns, name, or other gendered terminology.
- To treat someone as the incorrect gender.
- Mispronoun - To misgender someone by using an incorrect pronoun for them.
- Mix - A gender neutral honorific that can be used in the same manner as words like mister or miss.
- M.O.G.A.I. - Marginalized Orientations, Gender identities, And Intersex
- M.P.B. - Male Pattern Baldness
- M.T.F. - Male To Female
- M.T.N. - Male To Neutral
- M.T.X. - Male To [Unspecified Gender]
- Multigender - An umbrella term for all people with multiple genders, including bigender, trigender, polygender and pangender, as well as genderfluid people who identify as multigender.
- Muxe - A gender or social role in Zapotec culture that does not have an exact Western counterpart. A Muxe is a person who is initially assigned a male gender but who dresses and/or acts in ways often considered feminine. Muxes may identify as men, women, or another gender, and may or may not identify as trans.
- Mx. - The abbreviation of the honorific mix.