mou4 jyun4 mou4 gu3無緣無故无缘无故

Jyutpingmou4 jyun4 mou4 gu3

Yalemòuh yùhn mòuh gu

語句

Definition

For no reason at all; completely out of the blue.

colloquialdescriptionsdaily actions

How it's used

Used to describe events that occur without a clear cause or explanation. While it is a standard four character idiom, it is frequently interchangeable with the more colloquial 冇啦啦 in casual speech. It carries a slightly stronger sense of bewilderment or frustration compared to simply saying something happened suddenly.

Examples

keoi5佢mou4無jyun4緣mou4無gu3故faat3發pei4脾hei3氣，zan1真hai6係mok6莫ming4名kei4其miu6妙。

He lost his temper for no reason, it is truly baffling.

nei5你zou6做mat1乜mou4無jyun4緣mou4無gu3故ceng2請ngo5我sik6食faan6飯aa4呀？

Why are you treating me to a meal for no reason?

Common phrases

mou4無jyun4緣mou4無gu3故siu1消sat1失

disappear for no reason

mou4無jyun4緣mou4無gu3故faat3發fo2火

get angry for no reason

Common mistake

Learners often confuse this with 冇啦啦, which is strictly colloquial and carries a more informal, sometimes dismissive tone. Use 無緣無故 when you want to sound slightly more serious or when describing a situation that feels genuinely inexplicable.