What does El Psy Kongroo mean?

Nothing. エル・プサイ・コングルゥ is a made-up phrase Okabe uses to sign off, part of his mad-scientist act. It's said six times in season 1.

What does sekaisen mean in Steins;Gate?

世界線 (sekaisen) means world line: one version of how events play out. It's said 100 times in season 1, more than any other time travel word.

How many words are in Steins;Gate season 1?

59,580 spoken words across 24 episodes, using 4,291 different words. 36 words make up half of everything said, and 222 make up 75%.

Is Steins;Gate good for learning Japanese?

Yes, once you know the basics. It's a harder listen than a show like Frieren: it takes 36 words to reach half of the dialogue, versus 29 for Frieren, and it leans on science and time travel words. They repeat a lot, so they're quick to pick up.

Japanese Words in Steins;Gate: 50 Time Travel and Lab Words, Counted

I analyzed all 59,580 words spoken in season 1 of Steins;Gate, every one of its 24 episodes. Just 36 words make up half of everything said, and 222 make up 75%. That's the data-driven way to study: count every word, then learn exactly the ones the show says most. Below are 50 more: the time travel and lab words Steins;Gate says far more than other anime, each in Furoma, with kana above and romaji below.

Season 1, by the numbers

	Steins;Gate	Frieren
Episodes	24	28
Words spoken	59,580	61,997
Different words	4,291	4,075
Words that make up half the dialogue	36	29
Words that make up 67%	121	103
Words that make up 75%	222	206

Steins;Gate is a harder listen than Frieren: it takes 36 words to reach half of the dialogue, versus 29, and it leans heavily on science and time travel words. The 50 words below are only 3% of what's said, but they're the words that make it sound like Steins;Gate, and they repeat: you'll hear メール (message) about four times an episode.

The phrase: エル・プサイ・コングルゥ

El Psy Kongroo. Okabe signs off with it, usually on a phone call to no one. It doesn't mean anything: it's a made-up phrase, part of his mad-scientist act. It's said six times in season 1, and it's in the footer of every page on Yomikit.

The 50 words

Grouped by theme, most-said first within each group. Each card shows how many times the word is said in season 1, the episode where you first hear it, how much more Steins;Gate says it than other anime, and a strip of all 24 episodes, so you can see when it comes up.

Spoiler note: the strips show when words come up, and some words, like タイムリープ, first appear in the second half, so they hint at what's coming.

Time Travel

世界線 (せかいせん), sekaisen: world line

100 times, about four an episode

First heard in episode 1. Almost only in Steins;Gate.

タイムマシン, taimu mashin: time machine

99 times, about four an episode

First heard in episode 1. Almost only in Steins;Gate.

過去 (かこ), kako: the past

89 times, about four an episode

First heard in episode 1. 20.7× more than other anime.

世界 (せかい), sekai: world

84 times, about four an episode

First heard in episode 1. 2.5× more than other anime.

時間 (じかん), jikan: time

75 times, about three an episode

First heard in episode 2. 2.1× more than other anime.

#13

変える (かえる), kaeru: to change

59 times, about two an episode

First heard in episode 2. 6.7× more than other anime.

#14

戻る (もどる), modoru: to go back

54 times, about two an episode

First heard in episode 3. 2.1× more than other anime.

#16

未来 (みらい), mirai: the future

51 times, about two an episode

First heard in episode 2. 8.6× more than other anime.

#17

記憶 (きおく), kioku: memory

50 times, about two an episode

First heard in episode 1. 6.2× more than other anime.

#19

タイムリープ, taimu riipu: time leap

43 times, about two an episode

First heard in episode 11. Almost only in Steins;Gate.

#31

タイムトラベル, taimu toraberu: time travel

15 times, about once every two episodes

First heard in episode 2. Almost only in Steins;Gate.

#32

救う (すくう), sukuu: to save

15 times, about once every two episodes

First heard in episode 2. 2.0× more than other anime.

#39

過去改変 (かこかいへん), kako kaihen: changing the past

10 times, about once every two episodes

First heard in episode 7. Almost only in Steins;Gate.

#40

リーディングシュタイナー, riidingu shutainaa: Reading Steiner

9 times, about once every three episodes

First heard in episode 8. Almost only in Steins;Gate.

#43

ダイバージェンス, daibaajensu: divergence

7 times, about once every three episodes

First heard in episode 3. Almost only in Steins;Gate.

#44

運命 (うんめい), unmei: fate

7 times, about once every three episodes

First heard in episode 4. 2.3× more than other anime.

D-Mail and Phones

メール, meeru: message (text, email)

107 times, about four an episode

First heard in episode 1. 27.6× more than other anime.

送る (おくる), okuru: to send

99 times, about four an episode

First heard in episode 1. 14.0× more than other anime.

Dメール, dii meeru: D-mail

96 times, about four an episode

First heard in episode 6. Almost only in Steins;Gate.

#20

携帯 (けいたい), keitai: cell phone

43 times, about two an episode

First heard in episode 1. 11.1× more than other anime.

#21

電話レンジ (でんわレンジ), denwa renji: Phone Microwave

37 times, about two an episode

First heard in episode 1. Almost only in Steins;Gate.

#25

バナナ, banana: banana

26 times, about once an episode

First heard in episode 1. Almost only in Steins;Gate.

#27

電話 (でんわ), denwa: phone call

22 times, about once an episode

First heard in episode 4. 3.4× more than other anime.

#47

送信 (そうしん), soushin: sending, transmitting

6 times, about once every four episodes

First heard in episode 1. Almost only in Steins;Gate.

#48

ゲルバナ, gerubana: gel-banana

6 times, about once every four episodes

First heard in episode 1. Almost only in Steins;Gate.

The Lab and Science

#10

実験 (じっけん), jikken: experiment

65 times, about three an episode

First heard in episode 2. 16.8× more than other anime.

#11

助手 (じょしゅ), joshu: assistant (what Okabe calls Kurisu)

62 times, about three an episode

First heard in episode 3. Almost only in Steins;Gate.

#15

ラボ, rabo: lab

54 times, about two an episode

First heard in episode 1. Almost only in Steins;Gate.

#22

ラボメン, rabomen: lab member

33 times, about once an episode

First heard in episode 2. Almost only in Steins;Gate.

#28

未来ガジェット (みらいガジェット), mirai gajetto: Future Gadget

18 times, about once an episode

First heard in episode 1. Almost only in Steins;Gate.

#30

理論 (りろん), riron: theory

17 times, about once an episode

First heard in episode 1. Almost only in Steins;Gate.

#33

論文 (ろんぶん), ronbun: research paper

15 times, about once every two episodes

First heard in episode 1. Almost only in Steins;Gate.

#37

研究所 (けんきゅうじょ), kenkyuujo: laboratory

11 times, about once every two episodes

First heard in episode 1.

#38

天才 (てんさい), tensai: genius

11 times, about once every two episodes

First heard in episode 1. 3.7× more than other anime.

#41

人工衛星 (じんこうえいせい), jinkou eisei: satellite

9 times, about once every three episodes

First heard in episode 1. Almost only in Steins;Gate.

#42

科学者 (かがくしゃ), kagakusha: scientist

8 times, about once every three episodes

First heard in episode 1. Almost only in Steins;Gate.

#45

ブラウン管 (ブラウンかん), buraun kan: CRT (old TV tube)

7 times, about once every three episodes

First heard in episode 1. Almost only in Steins;Gate.

The Conspiracy and Okabe's World

SERN (セルン), serun: SERN

75 times, about three an episode

First heard in episode 2.

#12

IBN5100: the IBN 5100 computer

60 times, about three an episode

First heard in episode 2.

#18

機関 (きかん), kikan: the Organization

48 times, about two an episode

First heard in episode 1. Almost only in Steins;Gate.

#23

鳳凰院凶真 (ほうおういんきょうま), hououin kyouma: Hououin Kyouma, Okabe's mad-scientist name

32 times, about once an episode

First heard in episode 1. Almost only in Steins;Gate.

#24

マッドサイエンティスト, maddo saientisuto: mad scientist

29 times, about once an episode

First heard in episode 1. Almost only in Steins;Gate.

#26

作戦 (さくせん), sakusen: operation, plan

25 times, about once an episode

First heard in episode 4. 3.3× more than other anime.

#29

シュタインズ・ゲート, shutainzu geeto: Steins;Gate

18 times, about once an episode

First heard in episode 1. Almost only in Steins;Gate.

#34

秘密 (ひみつ), himitsu: secret

15 times, about once every two episodes

First heard in episode 1. 3.2× more than other anime.

#35

狂気 (きょうき), kyouki: madness

14 times, about once every two episodes

First heard in episode 1. Almost only in Steins;Gate.

#36

秋葉原 (あきはばら), akihabara: Akihabara

12 times, about once every two episodes

First heard in episode 1.

#46

エージェント, eejento: agent

7 times, about once every three episodes

First heard in episode 1. Almost only in Steins;Gate.

#49

エル・プサイ・コングルゥ, eru pusai konguruu: El Psy Kongroo

6 times, about once every four episodes

First heard in episode 1.

#50

陰謀 (いんぼう), inbou: conspiracy

6 times, about once every four episodes

First heard in episode 3. Almost only in Steins;Gate.

Read all 50 in Yomikit →

The nicknames

Steins;Gate runs on nicknames. Okabe gives everyone one, including himself, and you'll hear them constantly.

Nickname	Who	Times said
オカリン Okarin	Okabe Rintarou, from Okabe Rintarou	214
まゆしぃ Mayushii	what Mayuri calls herself	125
ダル Daru	Hashida Itaru	86
助手 joshu, "assistant"	what Okabe calls Kurisu	62
タイター Titor	John Titor, the time traveler online	41
クリスティーナ Christina	Okabe's other name for Kurisu	36
鳳凰院凶真 Hououin Kyouma	Okabe's mad-scientist name	32

If you like this, find the books

This page is my process on one show: count everything, then narrow in on exactly what to study. The books do the same for anime as a whole. I counted 3.3 million words across 120 anime to find the words worth learning first.

Watch Anime, Learn Japanese: the 210 words that make up 67% of the dialogue in 120 anime, as word cards, plus a top 1,000 list.
Top 200 Japanese Verbs in Anime: the 200 verbs that reach 80% of the verbs you'll hear, one page each.

Questions

What does El Psy Kongroo mean?: Nothing. It's a made-up phrase Okabe uses to sign off, part of his mad-scientist act. It's said six times in season 1.
What does sekaisen mean?: 世界線 (sekaisen) means world line: one version of how events play out. It's said 100 times in season 1.
How many words are in Steins;Gate season 1?: 59,580 spoken words across 24 episodes, using 4,291 different words.
Is Steins;Gate good for learning Japanese?: Yes, once you know the basics. It's a harder listen than Frieren, but its science and time travel words repeat a lot, so they're quick to pick up.

How I counted

I counted every word spoken in the Japanese subtitles of all 24 episodes of season 1, then compared each one with how often it's said across the 120 anime behind my books. The 50 here are the words Steins;Gate says far more than other anime.

More: Japanese Words in Frieren Learning Japanese with Anime How Many Words to Understand Anime