As a noun gender
is (grammar) a division of nouns and pronouns (and sometimes of other parts of speech), such as masculine / feminine / neuter, or animate / inanimate.
As a verb gender
is (sociology) to assign a gender to (a person); to perceive as having a gender; to address using terms (pronouns, nouns, adjectives) that express a certain gender or
gender can be (archaic) to engender.
As an adjective cissexual is
(lgbt|of a person) having a gender identity which matches one's birth sex; for example, identifying as male and having (been born with) male genitalia.