Cisplain 

To explain, without ever having felt the necessity to investigate the issue, that there are only two genders which are fixed and invariable for every individual at birth. Usually assumes equal lack of introspection on the part of transgender people who are likely to have spent their whole life questioning what gender means. The cisplainer is often shocked and angry when their cisplanation is not taken as absolute fact, criticized or even rejected altogether.

Some trans people also engage in cisplaining never having felt empowered to question the predominate cisgenderism of the society they were brought up in. This has been compared to a form Stockholm Syndrome.

An article is published in a newspaper describing how an individual, who was born male sex, has transitioned to a different gender. One of the first comments will cisplain:
"You can have as much surgery or medical treatment as you like but you'll always be a man (or woman)".

Cisplain by Transrilla January 6, 2013

cisplain 

When a cis-gendered, straight person attempts to explain, often incorrectly, the nuances of non-gendered language or non-heterosexuality to an LGBTQ+ person.

When a cis-gendered person "explains" something LGBTQ-related to an LGBTQ person, often in a condescending tone. It is also often presented in such a way that clearly belies it as a lesson they just ‘learned’ recently.

Example:
"Gurrrl, I went to a meeting at work today and my new boss cisplained that we are no longer using 'preferred’ pronouns."

cisplain by Stevinazo January 30, 2021

Civsplaining 

Civsplaining (blend word ‘civvy’ & informal form splaining of gerund ‘explaining’) is pejorative term meaning "(of a civ) to comment on or explain something to #squaddie in condescending, overconfident, often inaccurate or oversimplified manner"

I’m not #civsplaining you thick squaddie twat, I’m giving you guidance based on my considerable military knowledge gleamed from Commando comics & years of mucking thick military types, like MrSnaplegs, around.

Civsplaining by Bumsnorkler August 27, 2019

Cisplaining 

Not unlike mansplaining, Cisplaining is the act of a cisgender person explaining a transgenderone of a subject the latter is more knowledgeable in. The word is usually used to describe a situation in which the cis explains the trans of a trans-related subject or about a transgender experience, which the cisgender person, being cisgender, has never experienced.

Trans: "I think casting Scarlett Johansson to a role of a trans man is a very bad representation because-"
Cis: "Oh, nonsense! Johansson is a great actress, she will be a wonderful representation. So what if she is a woman?"
Trans: "That, right there, was the exact definition of cisplaining."

Cisplaining by theTransMusician July 4, 2018

Cisplaying 

the era of a transgender / nonbinary person where they were still in the closet, and externally cosplaying as cisgender.

I remember 2013. Those were the days I was cisplaying!

Cisplaying by spencerbits January 7, 2022

Cisplaying 

The act of cosplaying as someone of the same gender.

I, a cisgender male, shall be cisplaying as the Great Cornholio at this year's Comic-Con!

Cisplaying by childishbeat January 27, 2023

CISsplaining 

When a CIS person patronizes a CIS persons use of a pronoun or lack of inclusivity of a non binary gender.

*whispers* not all women have vaginas said the CISsplaining complainant

CISsplaining by @Stamishinc September 19, 2019