This is the 7313th most frequent Chinese word.
肆
"肆" means "to act recklessly" or "unrestrained," and can also refer to a shop or establishment in classical usage.
In this sentence, '肆' is part of the phrase '肆无忌惮', expressing unrestrained and unscrupulous actions.
他肆无忌惮地进入了房间。
He entered the room unscrupulously.
Here, '肆' is used in the word '肆虐', which means to ravage or devastate, indicating action that spreads destructively.
这个地区的洪水已经肆虐了三天。
The flood has ravaged this area for three days.
In this example, '肆' appears as part of a compound word, denoting a specific item or cultural element.