also: ときよ
noun
the times; an age; a day and age
Refers to the current era, social conditions, or the spirit of a particular period. Often used in set phrases like 時世に遅れる (fall behind the times).
時世に合わせてビジネスモデルを変える必要がある。
We need to change our business model to keep up with the times.
彼の考え方は時世に遅れている。
His way of thinking is behind the times.
時代 is the most common word for 'era' or 'period' and can refer to any historical period or a person's life stage. 時世 is more literary and emphasizes the social conditions or spirit of the current age.
時節 often refers to a season or a particular time of year, but can also mean 'the times' in a more general sense. 時世 is more abstract and focuses on the era's character.
Compound of 時 (time) and 世 (world, society). The reading じせい is the standard Sino-Japanese reading; ときよ is a rare native-Japanese reading.