marriage
marriage equality
masculine
masculine-of-centre
masculine presenting
Masculinising Hormone Therapy
meat and two veg
men who have sex with men
ménage à trois
metamour
metoidioplasty
metrosexual
mince
minge
misogyny
Miss Congeniality
MLM
monogamy
mononormativity
monosexual
Mother Superior
MSM
MtF
multigender
multisexual
multisexual spectrum
Mx.
nada to vada in the larder
naff
name change
an initialism of man-loving man.