periodic

a. 周期的, 定期的, 间歇(性)的, 循环的, 用完整句的, 高碘的
【医】 周期性的
【经】 定期的, 周期的

副词:periodically 

pe.ri.od.ic

adj.（形容词）
Having or marked by repeated cycles.
周期的，周期性的：循环往复的或以此为特征的
Happening or appearing at regular intervals.
定时的：在一定间歇期出现或发生的
Recurring or reappearing from time to time; intermittent.
间歇性的：不时重复发生或出现的；间歇的
Characterized by periodic sentences.
完句的：以循环句子为特征的

【引伸】
pe.riod.ically
adv.（副词）
<参考词汇><同义词>periodic,sporadic,intermittent,occasional,fitfulThese adjectives all mean recurring or reappearing now and then.Somethingperiodic occurs at regular or at least generally predictable intervals:
这些副词都意为不时重复出现的。某物为periodic ，是指发生在有规律的或至少通常可预料的间歇里：
例句：
periodic feelings of anxiety.
周期性焦虑。

Sporadic implies appearance or occurrence in scattered, irregular, unpredictable, or isolated instances:
Sporadic 指在杂乱的、不规律的、无法预测的或独立的情况下出现或发生：
例句：
a city subjected to sporadic bombing raids.
遭受零星轰炸的城市。

Intermittent describes something that stops and starts at intervals:
Intermittent 描述间歇性开始或停止的事：
例句：
intermittent rain showers. What isoccasional happens at random and irregularly:
间歇性暴雨。 Occational 形容随机、无规律发生的事情：

例句：
occasional outbursts of temper. Somethingfitful occurs in spells and often abruptly:
感情的突然爆发。 Fitful 的事发生在很短的时间中且常是突然的：

例句：
fitful bursts of energy.
能量的突然爆发期

Periodic has long been used loosely to mean .occasional, intermittent,. but this usage may be confusing for readers who are accustomed to using the word only in its narrower sense of .at regular or predictable intervals..Thus the writer who saidParker`s losses at the track were not covered by his periodic winners invited the (most likely unintended) inference that Parker had a system that enabled him to pick winners at regular intervals. Substitution ofoccasional in this context would have resolved the ambiguity.
Periodic 长时间以来不严谨地用于指.时常的，偶而的.， 但这个用法常常使那些习惯于将这个词用于.在有规律或可预测的间歇内.这个狭窄词义的读者迷惑。因此写帕克在赛跑中的失败不如他的胜利多 这句话的作者（主要是无意中）造成帕克有在定期赢得比赛的方法的推论。 在上下文中用occasional 代替应该能解决这种模棱两可的问题