jat1 wui4 si6一回事

Jyutpingjat1 wui4 si6

Yaleyāt wùih sih

名詞Uncommon

Definition

The same thing or matter; often used in contrast to imply that two issues are separate.

the same thing or matter
a separate matter entirely (often used in the structure 'X is one thing, Y is another')

colloquialpeoplecommunication

How it's used

This expression is frequently used in the pattern A 同 B 係一回事 to emphasize that two seemingly different things are essentially identical. Conversely, using 兩回事 highlights a clear distinction or lack of correlation between two topics. It is a very common way to clarify misunderstandings or to separate two issues that are being conflated in a discussion.

Examples

nei5你gong2講ge3嘅tung4同keoi5佢gong2講ge3嘅gan1根bun2本hai6係jat1一wui4回si6事。

What you said and what he said are fundamentally the same thing.

Common phrases

gan1根bun2本hai6係jat1一wui4回si6事

fundamentally the same thing

jyun4完cyun4全hai6係loeng5兩wui4回si6事

completely two different things

Common mistake

Learners often confuse this with the Mandarin usage, but in Cantonese, it is almost exclusively used in the contrastive structure with 兩回事 to express that things are either the same or completely unrelated.