あくび

Japanese

Etymology 1

Alternative spellings
欠 欠伸

Possibly from Old Japanese; first attested in the 新撰字鏡 (Shinsen Jikyō, “Newly Compiled Mirror of Characters”) of 898­­­–901 CE.

Appears to be derived as the 連(れん)用(よう)形(けい) (ren'yōkei, “stem or continuative form”) of the verb あくぶ, although this verb form isn't attested until the 枕草子 (Makura Sōshi, “The Pillow Book”) of 1002.

Pronunciation

• (Tokyo) あくび [àkúbí] (Heiban – [0])
• IPA^(key): [a̠kɯ̟ᵝbʲi]

Noun

あくび • (akubi) 

1. 欠, 欠伸: [from 901] a yawn, yawning

   欠(あく)伸(び)は移(うつ)るよ

   akubi wa utsuru yo

   A yawn can be contagious, isn't it

2. 欠: the 欠 element in kanji characters

Derived terms

• 欠(あく)伸(び)形(がた) (akubi-gata)
• 生(なま)欠(あく)伸(び) (nama akubi)

Idioms

• 欠(あく)伸(び)を噛(か)み殺(ころ)す (akubi o kamikorosu): “to bite down and kill a yawn” → to stifle a yawn

Verb

あくびする • (akubi suru) intransitive suru (stem あくびし (akubi shi), past あくびした (akubi shita))

1. to yawn

Conjugation

Conjugation of "あくびする" (See Appendix:Japanese verbs.)

Stem forms
Imperfective (未然形)	あくびし	akubi shi
Continuative (連用形)	あくびし	akubi shi
Terminal (終止形)	あくびする	akubi suru
Attributive (連体形)	あくびする	akubi suru
Hypothetical (仮定形)	あくびすれ	akubi sure
Imperative (命令形)	あくびせよ¹ あくびしろ²	akubi seyo¹ akubi shiro²
Key constructions
Passive	あくびされる	akubi sareru
Causative	あくびさせる あくびさす	akubi saseru akubi sasu
Potential	あくびできる	akubi dekiru
Volitional	あくびしよう	akubi shiyō
Negative	あくびしない	akubi shinai
Negative continuative	あくびせず	akubi sezu
Formal	あくびします	akubi shimasu
Perfective	あくびした	akubi shita
Conjunctive	あくびして	akubi shite
Hypothetical conditional	あくびすれば	akubi sureba
¹ Written imperative ² Spoken imperative

Etymology 2

For pronunciation and definitions of あくび – see the following entry.

【悪日】 [noun] unlucky day on a calendar [noun] any unlucky day

(This term, あくび, is an alternative spelling of the above term.)