春季 literally means 'spring season' and is a standard, formal term for the three-month period spanning March, April, and May in the Gregorian calendar (or the second lunar month through the fourth). The character 春 (chūn) means 'spring', evoking renewal, blossoms, and warmer weather, while 季 (jì) means 'season' — together they form a compound noun specifying one of the four annual seasons. It is commonly used in weather reports, academic calendars, agricultural planning, and seasonal product descriptions.

Unlike the more poetic or literary term 春天 (chūn tiān), which emphasizes the atmosphere or feeling of spring, 春季 is neutral and factual — preferred in official contexts like school terms ('春季学期'), climate data ('春季降雨量'), or business cycles ('春季促销'). It rarely appears in casual speech; native speakers often say 春天 instead when chatting informally about the season.