Words Written With Katakana in Japanese

In Japanese, sometimes a word is written with katakana instead of kanji or hiragana. This may happen for a number of reasons.

First and foremost, if a word does not have kanji, or if you want to write a word without kanji for some reason, it's generally better to write it with katakana instead of writing it with hiragana..

This happens because hiragana is normally used to write the stuff between words, such as grammatical particles and okurigana, and not to write the words themselves. So using katakana makes more sense, as that way it's easier to tell the words apart.

Given this, western loan-words, the gairaigo, are normally katakanized so they can be written in with the Japanese alphabet. For example: basu バス is how you'd write the English word "bus." You wouldn't write this word as basu ばす with hiragana, that'd be confusing.

To elaborate: basu wo tobasu バスを飛ばす means "to hurl a bus." Note that the katakana word (basu バス) is written differently from the okurigana of the verb "to hurl" (basu ばす). This way, it's easier to read, because you won't mistake one thing by the other.

The same thing also commonly happens with onomatopoeia. For example: dokidoki ドキドキ, *thump thump*, is written with katakana.

Certain simple native words which have kanji might get written with katakana instead because writing it with kana is much simpler than writing it with kanji. For example, dame 駄目 and dame ダメ, baka 馬鹿 and baka バカ.

It can also happen with slangs and neologisms to help differentiate them from similar words. For example: moteru 持てる means "be holding [something]." And from that word came moteru モテる, which's the same thing except replacing kanji with katakana, and meaning "to be popular [with girls]" instead of the act of holding anything.

The same happens with the words ikemen イケメン (origin: 行け面) and yandere ヤンデレ (origin: 病んデレ).

It's not always that a word is written with katakana just because it isn't written with kanji. There are cases where a word is written with hiragana instead. And sometimes hiragana and katakana can be used interchangeably. In such cases, the choice of katakana hint something.

Note above how katakana is normally used to write things by their sounds: in the first case we wrote a foreign word by its sound, and in the second case we wrote the sound of a thing. Following this, writing something with katakana might put emphasis on the sound of the syllables rather than on the meaning of what's written.

For example, when the reading of the kanji in a word are written on an online dictionary, it's usually written as katakana because it represents the sounds of the pronunciation.

In fiction, when there's a gaijin character, a "foreigner," and he tries to speak Japanese, katakana is sometimes used for their words to denote how they pronounce words awkwardly, in different tone. Similarly, robots can have their speech written with katakana instead to show they have a robotic voice.

Finally, sometimes a word may get written with katakana for aesthetic reasons. This happens because, simply put, katakana looks cool, and kanji looks classical. So writing the word ninja, for example, with kanji, you'd get an ancient ninja 忍者, very Japanese-y, but doing the same with katakana, you'd get a modern ninja ニンジャ, cutting-edge-with-sharp-edges.