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means adult in japanese. often used to describe anime pornography (it is NOT hentai. Hentai is a kanji (compound word) of the words Hen (strange, weird) and Tai (behavior, attitude, appearence etc etc) It is always used to describe a person and NEVER anime or manga) If someone was going to point out anime pornography, they would say "seijin-anime" or "seijin-manga". NOT "hentai"
average schmuck: hey man did u see that hentai NG is advertising?
smart person: its not hentai its seijin.
average schmuck: oh realy? I didnt know that
seijin by G-Imago130 July 10, 2006
Related Words
Seijin (星人, Star-people), which roughly translates 'Alien', are extra-terrestrial beings that originate from their respectively named planets, or are otherwise sentient aliens as opposed to simple Space Kaiju.

In neo-kaiju toys, this generally refers to sentient aliens.
Baltan is definitely my favorite seijin from Ultraman.

Have you seen the new glow-in-the-dark seijin release by Elegab? It's a lottery, so get your email in quick.
seijin by hellointerloper December 27, 2014
Seijin, which refers to humanoid aliens from space, means a ‘Person from the Stars’ in Japanese.
Ultraman is the most popular Seijin in both Japanese popular culture and the pop cultures of many nations in general.
Seijin by Snapper2001 May 15, 2023

oppai seijin 

Person who loves big tits (esp. anime titties)
Pedestrian oppai fan: Bro did you play this god tier nukige called oppai academy?
Based loli enjoyer: I ain't no oppai seijin ya dipshit. I only play lolige.
oppai seijin by pyun pyun April 14, 2022
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briefcake 

"Did you check out the briefcake in courtroom C?"
briefcake by Ben Frey April 6, 2006
Word of the Day on November 3, 2026
Brought to public attention by Bob Woodward and Carl Bernstein in the book on the fall of Richard Nixon, All The President’s Men, ratfucker was Nixon’s term for a political operative who sows chaos among opponents; an agent provocateur. It is thought to have originated among campus political rivalries at USC, and seems to have some usage in the US military.
Along with Nixon’s other ratfuckers, Roger Stone caused fights at otherwise peaceful Democratic Party protests to generate a false narrative that the Democrats were violent and dangerous.
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countrypolitan 

Term used to describe someone who is a mix of both rural (country) and urban (metropolitan) lifestyles/upbringings. He/she is typically equally comfortable in both settings and is able to seamlessly slip back and forth between the two, appreciating the characteristics of each.
That ol' gal of mine drives the 12 lane freeway during the week and a John Deere on the weekends. She likes opra and the Grand Ol' Opry. I love them countrypolitan women.
countrypolitan by MOChick November 7, 2006
Word of the Day on November 1, 2026

Witch Bath 

A bath consisting of a variety of slats, oils, soaps or any other added ingredients such as fruits, milks, herbs or any other spices for health or beautifying benifits.
She brought home alot of stuff and took it to the bathroom. She must be taking a witch bath.
Witch Bath by carnieboy30 October 26, 2020
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kinktober 

An excuse for people to write porn with different types of kinks throughout the month of October.

Smut Fanfiction
That chick doesn't write often but when she does, its for Kinktober.
kinktober by Kinkiest July 12, 2018
Word of the Day on October 30, 2026

proper lad 

a lad that is such a lad that he is a proper lad
person1:did you see bob
person2: ya he was a proper lad
Word of the Day on October 29, 2026
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