時・刻・秋|ときtoki[2]odaka (tail-high)

1. nountime; hour; moment刻 signifies a time of day; 秋 signifies an important time
   １２才さいの時とき彼かれは声変こえがわりした。↗

   His voice broke when he was twelve.
2. noun, adverboccasion; case
   車くるまを運転うんてんする時ときはいくら注意ちゅういしてもしすぎることはない。↗

   You cannot be too careful when you drive a car.
3. nounchance; opportunity; season
4. nounthe times; the age; the day
5. noun, grammartense

• Synonym時間じかんNeutralNeutral. Covers duration or clock hours, as in 「時間がない」「三時間」; 「とき」 instead points to an occasion or moment.
• SynonymタイムNeutralNeutral. Loanword mostly for timed results or a time-out, as in 「タイムを計る」; it is not the word for when something happens, the way 「とき」 is.
• Synonym時分じぶんWrittenWritten/formal. A somewhat old-fashioned word for an approximate time or period, as in 「子どもの時分」; in daily speech say 「頃」.
• SynonymころNeutralNeutral. An approximate period, as in 「子どもの頃」「三時頃」, stressing that the time is vague; 「とき」 can pin down a specific point.
• Synonym時刻じこくNeutralNeutral. A specific clock time, as in 「発車時刻」 — a single point on the timeline rather than an occasion.
• Synonym際さいFormalFormal. As きわ it means edge or brink; as さい, 「～の際」 marks the very moment of an event, mostly in formal settings, as in 「ご来店の際」.
• Synonym時期じきNeutralNeutral. A specific period or suitable season, as in 「この時期は忙しい」; feels more like a stretch of time than 「とき」.
• Synonym折おりWrittenWritten/formal. An occasion or opportunity, as in 「上京の折には」, typical of letters and polite set phrases.
• Related潮時しおどきWrittenWritten/formal. Originally the turn of the tide; now mostly a figurative right moment to start or end something, as in 「引退の潮時」.
• Related時機じきWrittenWritten/formal. The right moment to do something, as in 「時機を待つ」「時機を逸する」; more literary than 「とき」.
• Related時節じせつWrittenWritten/formal. Season or time of year, also the times or an opportunity, as in 「時節柄」「時節到来」.
• Related時代じだいNeutralNeutral. A historical era or stage of life defined by shared traits, as in 「江戸時代」「学生時代」; 「とき」 refers to a time in general, without that sense of a defined period.
• Related春秋しゅんじゅうWrittenWritten/formal. Literary word for years or age, as in 「春秋に富む」 (young, with a bright future ahead); not used in daily speech.
• Related年月としつきNeutralNeutral. Long stretches of accumulated time, as in 「長い年月がかかる」, focusing on how much time has passed.
• Related期きWrittenWritten/formal. A delimited period or installment, mostly as a suffix, as in 「第一期」「成長期」.
• RelatedひとときNeutralNeutral. A brief stretch of time, often with a pleasant nuance, as in 「楽しいひと時」.
• Related期間きかんNeutralNeutral. A span with a set start and end, as in 「募集期間」, stressing the bounded interval rather than an occasion.
• Related機会きかいNeutralNeutral. A chance to do something, as in 「いい機会」; matches only the opportunity sense of 「とき」.
• Related好機こうきWrittenWritten/formal. A good opportunity, as in 「好機を逃す」; more formal than 「チャンス」.
• Related場合ばあいNeutralNeutral. A case or condition, as in 「雨の場合は中止」, about hypothetical situations; 「とき」 is about time.
• Related歳月さいげつWrittenWritten/formal. Long, passing stretches of time, as in 「歳月が流れる」, with a wistful, reflective tone.
• Related際きわFormalFormal. As きわ it means edge or brink; as さい, 「～の際」 marks the very moment of an event, mostly in formal settings, as in 「ご来店の際」.

Default to 「とき」 for a time or occasion. Use 「時間」 for duration, 「頃」 for approximate times, 「時刻」 for clock times, 「場合」 for hypothetical conditions, and 「際」 (read さい) or 「折」 for formal occasions.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. （とき）時間じかん。
2. （とき）場合ばあい。