seasonal

Longman Dictionary of Contemporary English 5++朗文当代英语 5++LDOCE 5++朗文 5++sea·son·al /ˈsiːzənəl/ adjective [usually before noun] PERIOD OF TIMEhappening, expected, or needed during a particular season 季节性的，时令的，当令的 heavy seasonal rains 季节性的大雨seasonal workers/employment etc seasonal jobs in the tourist industry 旅游业的季节性工作

Examples from the Corpus

seasonal• The problem is that the number could be exceptionally hard to interpret because of seasonal adjustment difficulties.• This compares with 63 % at this time in 1997 and a five-year seasonal average of 53 %.• The seasonal charts are for late evenings, with the Sun far enough below the horizon for the sky to be dark.• In Temperate regions there are regular seasonal cycles, ultimately driven by the regular cycling of the Earth around the sun.• Of the dailies, Today's circulation has registered the worst seasonal drop, falling to 466,631 from 513,673.• waffles served with fresh seasonal fruits• seasonal variation in rainfall levels• In other words, they have become instinctively aware of changes in daily and seasonal variations in temperature.seasonal workers/employment etc• The seasonal workers and outworkers do not receive the security or the minimal benefits that are available to regular workers.• Men who had been seasonal workers formerly began talking of going stone-gathering and ditching during the winter.• For many seasonal workers, the biggest drawback can be the irregular hours and erratic schedules.From Longman Business Dictionaryseasonalsea‧son‧al /ˈsiːzənəl/ adjective1seasonal adjustment/ change/variation etcCOMMERCE adjustments you make or changes that happen because of the situation during a particular period of the year, that is not typical of the rest of the yearUnemployment figures were down during the summer months, even after seasonal adjustment.2seasonal business/employment/workers etcCOMMERCEHUMAN RESOURCES happening or needed only at a particular time of yearThousands of agricultural laborers arrive to do seasonal work on American farms. —seasonally adverbFrance’s seasonally adjusted foreign trade deficit