Several parts combine into one character.

Oracle bone 年 shows a person (人) carrying ripe grain stalks (禾) on their back — the harvest. The encoded definition: "one year" = "one cycle of grain ripening". For ancient agricultural China, the calendar was the harvest. The character has stylized over millennia until the human-with-grain image is barely visible, but the etymology is essential for understanding why "year" and "harvest" share so many compound roots in CJK languages. Identical across 繁體 / 新字体 / 简体.

Mandarin: nián, rising 2nd tone. 年 covers calendar year, age, and harvest equally: 今年 (jīnnián, this year), 去年 (qùnián, last year — note: 去 here means "past", not "go"), 明年 (míngnián, next year), 年龄 (niánlíng, age), 年纪 (niánjì, age — colloquial), 年级 (niánjí, grade in school), 新年 (xīnnián, New Year). 过年 (guònián) literally "to pass the year" = to celebrate Chinese New Year, which still anchors on the spring agricultural calendar despite urban modernization.

Japanese: on-reading ネン (nen) — 来年 (rainen, next year), 去年 (kyonen, last year), 学年 (gakunen, school year), 年齢 (nenrei, age), 年金 (nenkin, pension), 一年 (ichinen, one year). Kun-reading とし (toshi) for emotional/personal age — お年 (o-toshi, "your honored age"), 年寄り (toshiyori, elderly person), 年取る (toshi toru, to grow old). The split between ネン (formal/calendar) and とし (personal/lived) is characteristic of Japanese.

The Japanese New Year お正月 (oshōgatsu) is one of the most important annual events, and the greeting 明けましておめでとうございます ("Happy New Year") uses the verbal sense of "year-opening". 年賀状 (nengajō, New Year postcards) are sent by the millions every December.

Memory aid: a person carrying grain — the harvest defines the year.