# とんでもない
## Japanese
### Etymology

Many sources consider this to be a shift from 途でもない (to de mo nai, literally “that is not even the way”, idiomatically “extraordinary, unexpected, unreasonable”) or とでもない (to de mo nai, literally “that's not even [whatever came before]”, where the to here is the quotative particle to in reference to whatever was just said previously).
However, citations for tondemonai precede those for todemonai by several decades (tondemonai cited to 1586–99, todemonai to 1638), pointing instead to tondemonai as the original form, and to de mo nai as a later development.
An analysis of the earliest texts indicates that this expression arose first in eastern Japanese dialects. Eastern dialects have a tendency to pre-nasalize voiced consonants, which would suggest that the initial tonde may indeed be to de (from either noun 途 (to, “way”) or particle と (to, quotative)).
While the ない (-nai) ending does appear to be 無い (nai, “not; is not”), there are no historical attestations of とんでも (tondemo) used separately. The term トンデモ (tondemo, “outrageous, unexpected”) is derived from とんでもない (tondemonai) only in relatively modern usage, such as in the now-dated expression とんでもハップン (tondemo happun) cited to 1950.
Despite surface similarities, the tonde here is almost certainly not derived from とんだ (tonda, “extraordinary, unexpected”).

### Pronunciation

* (Tokyo) とんでもない [tòńdémónáꜜì] (Nakadaka – [5])
* IPA: [tõ̞nde̞mo̞na̠i]
* Tokyo pitch accent of inflected forms of 「とんでもない」
Source: Online Japanese Accent Dictionary :
| Stem forms ||||
| Continuative (連用形) | とんでもなく | とんでもなく | [tòńdémónáꜜkù] |
| Terminal (終止形) | とんでもない | とんでもない | [tòńdémónáꜜì] |
| Attributive (連体形) | とんでもない | とんでもない | [tòńdémónáꜜì] |
| Key constructions ||||
| Informal negative | とんでもなくない | とんでもなくない | [tòńdémónáꜜkùnàì] |
| Informal past | とんでもなかった | とんでもなかった | [tòńdémónáꜜkàttà] |
| Informal negative past | とんでもなくなかった | とんでもなくなかった | [tòńdémónáꜜkùnàkàttà] |
| Formal | とんでもないです | とんでもないです | [tòńdémónáꜜìdèsù] |
| Conjunctive | とんでもなくて | とんでもなくて | [tòńdémónáꜜkùtè] |
| Conditional | とんでもなければ | とんでもなければ | [tòńdémónáꜜkèrèbà] |

### Adjective

とんでもない • (tondemonai) -i (adverbial とんでもなく (tondemonaku))
* [from roughly 1586] unbelievable, unreasonable, extraordinary, completely unexpected, outrageous, preposterous
    Synonyms: 途方もない (tohō mo nai), 思いがけない (omoigakenai), 意外 (igai), とんだ (tonda), 以ての外 (motte no hoka), 途轍もない (totetsu mo nai)
    俺(おれ)はとんでもないことをしてしまった。
       Ore wa tondemonai koto o shite shimatta.
       I did something totally outrageous.
* [from 1905] not at all
    「ありがとうございます。」「いやいや、とんでもないです。」
       “Arigatō gozaimasu.”“Iya iya, tondemonai desu.”
       "Thank you." "No no, not at all."

#### Usage notes

In older texts, this was treated as a single integral term, with the ない (-nai) ending treated as inseparable. This was used in 丁寧語 (teineigo, “the polite register”) in constructions such as とんでもないことです (tondemonai koto desu) or とんでもないことでございます (tondemonai koto de gozaimasu).
In modern usage, the ない (-nai) ending is treated as separable, and polite constructions may replace the ない (-nai) ending with the negative form of the copular verb instead, such as in とんでもありません (tondemo arimasen) or とんでもございません (tondemo gozaimasen).

#### Inflection

Stem forms :
| Imperfective (未然形) | とんでもなかろ | tondemonakaro |
| Continuative (連用形) | とんでもなく | tondemonaku |
| Terminal (終止形) | とんでもない | tondemonai |
| Attributive (連体形) | とんでもない | tondemonai |
| Hypothetical (仮定形) | とんでもなけれ | tondemonakere |
| Imperative (命令形) | とんでもなかれ | tondemonakare |
| Key constructions ||||
| Informal negative | とんでもなくない | tondemonaku nai |
| Informal past | とんでもなかった | tondemonakatta |
| Informal negative past | とんでもなくなかった | tondemonaku nakatta |
| Formal | とんでもないです | tondemonai desu |
| Formal negative | とんでもなくないです | tondemonaku nai desu |
| Formal past | とんでもなかったです | tondemonakatta desu |
| Formal negative past | とんでもなくなかったです | tondemonaku nakatta desu |
| Conjunctive | とんでもなくて | tondemonakute |
| Conditional | とんでもなければ | tondemonakereba |
| Provisional | とんでもなかったら | tondemonakattara |
| Volitional | とんでもなかろう | tondemonakarō |
| Adverbial | とんでもなく | tondemonaku |
| Degree | とんでもなさ | tondemonasa |

#### Derived terms

* トンデモ (tondemo-): (prefix) outrageous, crazy

### References

* 1 2 Matsumura, Akira, editor (2006), 大辞林 [Daijirin] (in Japanese), Third edition, Tokyo: Sanseidō, →ISBN
* 1 2 Kindaichi, Kyōsuke et al., editors (1997), 新明解国語辞典 [Shin Meikai Kokugo Jiten] (in Japanese), Fifth edition, Tokyo: Sanseidō, →ISBN
* 1 2 “とんでもない”, in デジタル大辞泉 [Digital Daijisen]‎ (in Japanese), Tōkyō: Shogakukan, updated roughly every four months
* 1 2 とんでもない, in 日本辞典 (Nihon Jiten, “Japan Dictionary”) (in Japanese)
* 1 2 3 とんでもない, in 語源由来辞典 (Gogen Yurai Jiten, “Etymology Derivation Dictionary”) (in Japanese)
* ↑ “とでもない”, in デジタル大辞泉 [Digital Daijisen]‎ (in Japanese), Tōkyō: Shogakukan, updated roughly every four months
* 1 2 “とんでもない”, in 日本国語大辞典 [Nihon Kokugo Daijiten]‎ (in Japanese), concise edition, Tokyo: Shogakukan, 2006
* ↑ “とんでもハップン”, in 日本国語大辞典 [Nihon Kokugo Daijiten]‎ (in Japanese), concise edition, Tokyo: Shogakukan, 2006
* ↑ “とんでもハップン”, in デジタル大辞泉 [Digital Daijisen]‎ (in Japanese), Tōkyō: Shogakukan, updated roughly every four months
* ↑ NHK Broadcasting Culture Research Institute, editor (1998), NHK日本語発音アクセント辞典 [NHK Japanese Pronunciation Accent Dictionary] (in Japanese), Tokyo: NHK Publishing, Inc., →ISBN