No varying with the seasons; constant, permanent.(adjective)
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Use "nonseasonal" in a sentence
"The federal government will make approximately 125,000 new hires for full-time, nonseasonal jobs during this fiscal year, according to new estimates."
"Light therapy has been used previously for people with significant seasonal affective disorder as well as nonseasonal depression."
"Not content with earning three Michelin stars for this temple of experimentation and a strong nonseasonal, molecular approach, he has opened a new restaurant in the heart of London, which, rather daringly, is inspired by historical English cuisine."