“传统节日”常见的英文表达是 traditional festivals 或 traditional holidays。
traditional festivals：更侧重于文化习俗、传统仪式等方面，强调节日所承载的文化传承意义。例如：Many traditional festivals in China are closely related to agricultural activities.（中国许多传统节日与农事活动密切相关。）
traditional holidays：侧重于假期、休假日的层面，同时包含传统意味。例如：We usually have family reunions during traditional holidays.（在传统节日期间，我们通常会举行家庭聚会 。）