sea·son·al (sē'zə-nəl) adj. Of or dependent on a particular season. sea'son·al'i·ty (-zə-nāl'ĭ-tē) n., sea'son·al·ly adv.
Usage Note: Seasonal and seasonable, though closely related, have different uses. Seasonal applies to what depends on or is controlled by the season of the year: a seasonal rise in employment.Seasonable applies to what is appropriate to the season (seasonable clothing) or timely (seasonable intervention in the dispute). Rains are seasonal if they occur at a certain time of the year; they are seasonable at any time if they save the crops.