Oldness and antiquity with

The kanji 古 has the straightforward meaning of something old or from long ago.

Etymology

In its later written form, this kanji is shown as 十 over 口. Traditional explanations connect it with something passed down through many mouths across many generations, making it ancient and longstanding.

Antiquity

(Ancient times)

古代(こだい) means ancient times or antiquity, especially in historical writing.

It combines 古 (old) with 代 (generation) to show an old age of history.

Manga panel from カードキャプターさくら showing example of Dueling like in Ancient Rome with 古代.
カードキャプターさくら » Volume 3 » Page 21

Li seems fired up over something with Sakura. Yamazaki suggests whatever the issue is be settled when they play badminton during that day’s physical education class. Li asks why things have to be settled via badminton.

山崎(やまざき):
「知(し)らないの?バドミントンっていうのはね 古代(こだい)ローマから伝(つた)わる由緒(ゆいしょ)正(ただ)しい決闘(けっとう)方法(ほうほう)でね」
“You don't know? Badminton is a time-honored method of dueling that has been passed down since ancient Rome.”
「負(ま)けたほうはもう それはひどいめに……」
“The loser suffers a truly terrible fate.”
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Classical Texts

(Classical Japanese)

古文(こぶん) means classical Japanese writing or literature, especially works from the Edo period or earlier. In school, it also names the study of such texts.

It combines 古 (old) with 文 (writing) to show old writing or a classical text.

Manga panel from あずまんが大王 showing example of Studying classical Japanese with 古文.
あずまんが大王 » Volume 1年生 » Page 34

Following the a midterm exam, Yomi asks Tomo how it went.

とも:
「古文(こぶん)はなんのために勉強(べんきょう)するの?」
“What's the point of studying classical Japanese?”
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Practice and Learning

(Practice)

稽古(けいこ) means practice or training, especially in martial arts, performing arts, and other traditional disciplines. It can also mean a lesson or training session in one of those arts.

It combines 稽 (examine) with 古 (old) to show practice rooted in studying established ways.

Example 1 of 2: Koto lessons with 稽古
Example 1 of 2
Manga panel from 名探偵コナン showing example of Koto lessons with 稽古.
名探偵コナン » Volume 6 » Page 27

Hired to confirm whether a client’s wife is having an affair, Kogoro reveals a candid photo he took of the wife with another man. The client mentions he let his staff take a break so they wouldn’t know about Kogoro’s visit. Kogoro asks if that includes the client’s wife.

伝次郎(でんじろう):
「いや… 稲子(いねこ)は琴(こと)の稽古(けいこ)があるといって昼前(ひるまえ)に勝手(かって)に出(で)かけたよ」
“No... Ineko said she had a koto lesson and went out on her own before noon.”
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Example 2 of 2: Training for a judo match with 稽古
Example 2 of 2
Manga panel from 俺物語!! showing example of Training for a judo match with 稽古.
俺物語!! » Volume 2 » Page 56

Members of the judo team plea for Takeo to help them in their upcoming match against a rival high school. Takeo quickly accepts their request, but Sunakawa considers how this will impact Takeo’s new relationship with Yamato.

砂川(すなかわ):
「おまえ試合(しあい)の稽古(けいこ)するんだったら しばらく大和(やまと)さんに会えなくなっちゃうんじゃない? 1(いっ)か月(げつ)くらい?」
“When you're training for the match, won't you be unable to see Yamato for a while? For about a month.”
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