1. Pertaining to one of the periods into which a year is naturally divided as marked by its temperature, moisture, etc.: The seasonally times of spring, summer, autumn, and winter are variations of wet and dry climates.
2. Conveying that part of the year when particular trades, professions, or businesses have the greatest activities: Christmas is one of the more seasonally active times for sales of products by stores.

Some restaurants seasonally change their menus at various times.

3. Etymology: from Latin satio, sationis, "a sowing" from sero, satum, "to sow".