Seasonal \Sea"son*al\, a.
1. Of or pertaining to the seasons.
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2. Occurring or being used in a specific season; as, seasonal
items for sale.
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{Seasonal dimorphism} (Zool.), the condition of having two
distinct varieties which appear at different seasons, as
certain species of butterflies in which the spring brood
differs from the summer or autumnal brood.
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