季節
きせつ
kisetsu
= season
Kisetsu is the word for a season, and in Japan it does more conversational work than the English word does.
Kisetsu (季節) refers to a season as one of the periods that make up the year. Shiki (四季) refers to the set of four seasons taken together, as a single concept rather than one particular season. The phrase 季節が変わる (kisetsu ga kawaru) means the season is changing, and kisetsu ga meguru (季節がめぐる) describes the seasons coming round again. The word learners most often confuse this with is jiki (時期), which means a period or time of year in a looser sense. Jiki can point at any stretch of time, such as a busy period at work or a good time to travel, while kisetsu specifically means one of the seasons themselves.
Kisetsu is a noun and never takes な or い directly — kisetsuna and kisetsui are not words. In ordinary speech, seasonal is kisetsu no (季節の) plus a noun, as in kisetsu no yasai (季節の野菜, seasonal vegetables). There is a derived adjectival form, kisetsuteki (季節的), but it belongs to analytical writing such as kisetsuteki na hendou (季節的な変動, seasonal fluctuation), not to everyday description. A related word worth knowing is kisetsukan (季節感), a sense of the season — it is used when praising food, clothing, or decoration that fits the time of year, and English does not have a single neat equivalent for it. Separately, shun (旬) is the more specific word for a food being at its seasonal peak; learners often reach for kisetsu in this context when shun is actually the word they mean.
Everyday use
季節が変わってきましたね。
Kisetsu ga kawattekimashita ne.
The season is starting to change, isn’t it.
Casual / Social Media
コンビニでもう季節のドリンクが出てる!
Konbini de mou kisetsu no dorinku ga deteru!
The seasonal drinks are already out at the convenience store!
Formal / Cultural context
季節の変わり目ですので、どうぞご自愛ください。
Kisetsu no kawarime desu node, douzo go jiai kudasai.
As the seasons are changing, please take good care of yourself.
Daily life in Japan is framed around the season to a degree that surprises many learners. Convenience store shelves, restaurant menus, and even snack packaging change with the kisetsu, so a walk through a shop can double as a quiet calendar check — coffee chains rotate their drink lineups, supermarkets reposition their produce, and department stores swap out their window displays.
Kisetsukan (季節感) functions almost as a value judgment in how food and clothing are chosen and presented. A dish plated with a single seasonal leaf, or a fabric pattern that nods to the current time of year, gets complimented specifically for having good kisetsukan — the sense that it belongs to this particular moment in the year rather than being generic.
Formal and semi-formal writing carries its own seasonal convention: letters and business messages often open with a line about the current kisetsu before getting to the main content, similar to how English letters might open with a comment on the weather but more fixed in form. These openers are fixed enough that a reader recognizes the form before the content — the seasonal line signals politeness rather than conveying news about the weather.