How to say "summer" in Japanese

Choosing the right word

夏なつJLPT N5approx.Common
noun, adverbThe everyday word for summer as the season of the year, covering the season itself and particular summers such as last summer or this summer; it is the usual choice in speech and writing.
この夏なつ最高さいこうの暑あつさだ。↗
It is the hottest this summer.
サマーCommon
nounThe English loanword; it turns up chiefly in borrowed or fashionable phrasing rather than as an ordinary noun for the season, so for 'summer' itself 夏 is nearly always the word you want.
夏季かきCommon
nounA formal, written-style word for the summer season as a whole, typical of announcements, schedules and official notices; choose it when a businesslike tone is wanted rather than in everyday conversation.

Use 夏 for the season in ordinary speech and writing, 夏季 when a formal, written tone suits the summer season, and 「サマー」 only within borrowed or stylish phrasing, since it is marginal as a standalone word.

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

Japanese equivalents

夏なつsummer
サマーsummer
夏季かきsummer season
夏げsummer (on the lunisolar calendar: 16th day of the 4th month to the 15th day of the 7th month)
九夏きゅうかsummer
アナログ加算器アナログかさんきsummer
炎陽えんようsummer sun
木の暗このくれsummer

JLPT vocabulary levels are community estimates, not official (no official lists have been published since the 2010 revision).

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