決める

• (less common) 極める
• (to take drugs): キメる

Derived as the transitive form of Old Japanese verb 決む (kimu, “to decide something, to conclude something; to be decided, to be concluded”).[1][2][3]

The source verb kimu appears to follow a common pattern in Old Japanese verbs where the bare form is either transitive or intransitive, depending on context. This pattern persists in some modern verbs, such as つく (tsuku). Many of these Old Japanese verbs developed explicit transitive and intransitive forms, with one group adopting an -aru on the end for the intransitive (as the 未然形 (mizenkei, “irrealis or incomplete form”) ending in -a + the conjugating る (ru) as the basic spontaneous or passive verb ending), and an -eru on the end for the transitive (as the 已然形 (izenkei, “realis or potential form”) + the disappearing る (ru) as a generic verb ending).

• Kun’yomi
  • (Tokyo) きめる [kìmérú] (Heiban – [0])[2][4]
  • (Tokyo) きめる​ [kìmérúꜜ] (Odaka – [3])[4]
  • IPA^(key): [kʲime̞ɾɯ̟ᵝ]

決める (transitive, ichidan conjugation, hiragana きめる, rōmaji kimeru)

1. to make a choice between multiple alternatives, to decide

   日 (に)時 (ちじ)を決 (き)める

   nichiji o kimeru

   to choose a time

   This verb also has many idiomatic shades of meaning based on the underlying sense of decide:

   1. to decide to do something: to do something on purpose

      横 (おう)着 (ちゃく)を決 (き)める

      ōchaku o kimeru

      to decide to shirk → to shirk intentionally

   2. to perform a maneuver, to carry out a tactical action

      スクイズを決 (き)めた

      sukuizu o kimeta

      We've decided on the squeeze → The squeeze play is on.

   3. to decide on an opinion: to believe in an opinion firmly

      彼 (かれ)を犯 (はん)人 (にん)と決 (き)めてかかる

      kare o hannin to kimete kakaru

      I know he was the murderer from the very beginning

   4. to decide on a common course of action: to be accustomed to do, to do habitually

      朝 (ちょう)食 (しょく)はパンに決 (き)めている

      chōshoku wa pan ni kimete iru

      I always eat bread for breakfast

      This usage takes the particle に (ni), and usually uses the -ている (-te iru) progressive form.

   5. to make an impressive or attractive physical appearance, usually by grooming oneself or making some unusual gestures

      黒 (くろ)い背広 (せびろ)と紺色 (こんいろ)のシャツで決 (き)める

      kuroi sebiro to kon'iro no shatsu de kimeru

      to decide on one's appearance with a black suit and indigo shirt → to be set or look sharp in a black suit and indigo shirt

   6. (derogatory) to decide to eat or use something: to eat, to intake, to consume

      シャブをキメる

      shabu o kimeru

      to use addictive drugs

• 決 (き)まる (kimaru): to be decided, to be concluded, to be brought to a resolution (intransitive form)