1.
frequently; often; at short intervals
Describes something that happens many times or at short intervals. More formal than よく and emphasizes the high frequency or repetition.
地震が頻繁に起きる。
Earthquakes occur frequently.
最近、頻繁に頭痛がする。
Lately I've been getting headaches frequently.
この交差点では事故が頻繁に発生しているので信号機が設置された。
Accidents were occurring so frequently at this intersection that a traffic light was installed.
USAGE:
頻繁に is more formal and emphatic than よく (often). It stresses the high frequency or closeness of intervals, and is common in news, reports, and formal writing.
GRAMMAR:
頻繁 is a na-adjective that can also be used predicatively: 連絡が頻繁だ (Contact is frequent). The adverbial form 頻繁に is more commonly used.
COMPARISON:
- よく — general "often," neutral register
- 頻繁に — emphasizes high frequency, somewhat formal
- しょっちゅう — "all the time," informal, sometimes implies annoyance
- しばしば — "often," literary/written style