How to know the meaning/usage of 一


Well I'm a begginer, how do I know if **一** means ichi/itsu or its used for
lengthening the word??

in **tenkaichi** (dragon ball) **ichiraku ramen** (naruto) the **一** is used
there because it means best or one

I'm wondering if **一** can be used in spelling instead of **いち** even though
the sentence doesn't mean one/best

and when i read some titles of eps, i don't know if the **一** means _1_ or its
used for _lengthening_ the word




When it appears in a kanji compound (or some compounds which mix kanji and
kana), it is the kanji character for
'[one](https://www.weblio.jp/content/%E4%B8%80)' 一. This can be read as いち or
ひと depending on the context. When it appears in kana words (mostly katakana),
it is called a **chōonpu** ([超音符](https://en.wikipedia.org/wiki/Ch%C5%8Donpu))
and functions to lengthen the previous vowel.

> 日本一 (にほんいち) (kanji compound)  
>  ケーキ (keeki) (katakana)  
>  おーい (ooi) (hiragana)  
>  万が一 (まんがいち) (mixed kanji and kana)

