嚯
嚯 can be an interjection or a sound-imitative word. Let's look at both of them.
The interjection 嚯
Pay attention
An interjection (感叹词) is a word or expression that occurs as an utterance on its own and expresses a spontaneous feeling or reaction. It expresses feelings and emotions but does not name them. It is usually placed at the beginning of a sentence.
The interjection 嚯 
expresses:
1) a loud laugh: “haha”.
expresses:
1) a loud laugh: “haha”.Examples
嚯、嚯、嚯! 你也太搞笑了
Haha, you are funny too!
huò, huò, huò! nǐ yě tài gǎoxiào le
2) surprise or delight. It can be translated as “wow”, “oh!”.
Examples
嚯，原来你在这儿！
Wow, so you're here!
huò, yuánlái nǐ zài zhèr
嚯，你们来得真早啊！
Oh! You came so early!
huò, nǐmen lái de zhēn zǎo a
The sound-imitative word 嚯
Pay attention
Sound-imitative words are also called "onomatopoeia" (象声词).
嚯 also can be an imitation of the sound of a rapid movement: “whoosh”.
also can be an imitation of the sound of a rapid movement: “whoosh”.Examples
他一听到了好消息就嚯地跑去了
Whoosh! He ran away as soon as he heard the good news.
tā yī tīngdào le hǎo xiāoxi jiù huò de pǎoqù le