Splaining 

Explaining something in a slightly condescending, patronizing manner, while a) assuming the person you're talking to isn't knowledgeable about the subject, b) likely believing you know more about it than you actually do, and c) thinking they must need to hear your wisdom.

Can be used as a suffix to indicate the topic being 'splained, e.g., dog-splaining, car-splaining

#1)

"I just got a puppy and you would not believe how many people dog-splain to me how I should train it or what its breed is like. They all think they're expert animal trainers."

#2)

Person A: "Hey man, I got a chance to look at your YouTube videos. You know, channels get more views when they have attention grabbing thumbnails. You might want to try that. Also, one way to get more engagement is to have an introduction that..."

Person B: "Dude, stop YouTube-splaining me. I run my own channel. You think I don't know about all that stuff already?"

Splaining by CommanderFerret March 18, 2021

Splaining 

Kinda like mansplaining or womansplaining but just splaining in general. When someone explains something to you assuming that you have no knowledge of the subject.

Splaining:
you: breaths
splainer: well actually the origin of ... blah blah blah
you: i... i know
splainer: no, actually ... (a bunch of useless information you didn't ask for)

Splaining by 3 and also a half of a bear May 6, 2018

'Splaining 

The direct Mexican translation of explaining as used by the President for Life of Mexico Ricky Ricardo, married to Lucy... who everyone apparently loves.

After Ricky walks in on some of Lucy's antics/shenanigans...

Lucy: OH RICKY, YOU'RE HOME!

Ricky: Lucy, you got some 'splaining to do!

'Splaining by Michael Steamley May 23, 2008

Shame-splaining 

Shaming or otherwise guilting another party for not sharing the same belief or value system as yourself in an attempt to alter their opinion. This can involve haphazard labeling, or insults of the cursory nature.

James engaged in shame-splaining by calling Pete narrow-minded for his beliefs on gun control, before expressing how gun control should work and how wrong Pete was.

Shame-splaining by ModernMichael May 26, 2020

Post-splaining 

Post-splaining- noun, gerund; when your political opinions are so brilliant, clever & flawless, posting them on all social media platforms is required so all the world can know the real truth.

I don't like it when my Facebook friends are post-splaining what I should think about the President's politics

Post-splaining by Mobilepreacher January 21, 2020

Nola-splaining 

When someone tells you how shit you are at something, without acknowledging you’re feelings, or the fact that you don’t care about this opinion.
It’s only Nola-splaining when the opinion is in no way whatsoever constructive or useful

P1: “oh look, I made this drawing”
P2: “it’s really bad”
P1: “what? Why?”
P2: “it just... looks bad.”
P3: “god she’s Nola-splaining again.”

Nola-splaining by Angry friend. August 20, 2019

Chef-splaining 

when a person who watches too many Tasty videos tries to explain cooking to a chef

While watching a Tasty video on how to make a jiggly fluffy cheesecake, Isay was chef-splaining to her friend Ken the Chef what folding in beaten egg whites into batter means.

Chef-splaining by crustaceanlover December 6, 2017