The idiom "a cold fish" is used to describe someone who is unfriendly, unemotional, and unapproachable. It means that the person is not warm or friendly towards others and doesn't show any emotions or feelings.
For example, if someone says "I tried to talk to her, but she was a cold fish," it means that the person they were trying to talk to was distant and unresponsive.
This idiom is often used to describe people who are difficult to get to know or who don't show much interest in socializing. It can also be used to describe someone who is unresponsive to romantic advances or who seems uninterested in forming close relationships with others.
In short, "a cold fish" is a negative term used to describe someone who is not friendly or approachable.
• I can't make friends with her, she's a cold fish.
• My boss is a cold fish, it's hard to talk to him about anything.
• She comes across as a cold fish, but once you get to know her she's very warm.
• Despite her success, many people find her to be a cold fish and hard to approach.
• I find it difficult to connect with him, he's a bit of a cold fish.
• I tried to strike up a conversation with him, but he was a real cold fish.