This is the 4379th most frequent Chinese word.
惊
"惊" means "to startle" or "to be shocked."
Here, '惊慌' uses '惊' to denote sudden fear or panic in response to something unexpected.
他听到这个消息后大为惊慌。
He was greatly alarmed after hearing the news.
In '惊人', '惊' expresses an impression of amazement or astonishment due to something extraordinary.
这个画面真是惊人！
This scene is truly astonishing!
The compound '惊叹' utilizes '惊' to signal being astonished or awed by something magnificent or impressive.