- 1. [adj-na, n] cool-headed; level-headed; hard-headed
Conjugation — Adjective (―na)
This word itself does not change -- these are forms of the copula だ ("to be") attached to it.
| Attributive (before a noun) | れいてつな | (reitetsuna) |
| Non-past, plain | れいてつだ | (reitetsuda) |
| Non-past, polite | れいてつです | (reitetsudesu) |
| Past, plain | れいてつだった | (reitetsudatta) |
| Past, polite | れいてつでした | (reitetsudeshita) |
| Negative, plain | れいてつじゃない | (reitetsujanai) |
| Negative, polite | れいてつじゃないです | (reitetsujanaidesu) |
| Past negative, plain | れいてつじゃなかった | (reitetsujanakatta) |
| Past negative, polite | れいてつじゃなかったです | (reitetsujanakattadesu) |
| Te-form | れいてつで | (reitetsude) |
| Conditional (―nara) | れいてつなら | (reitetsunara) |