Explanation
Expresses the extreme of something; 'nothing can be more ... than this'.
Formation
い-Adjective + といったらない / な-Adjective + だといったらない / Noun + だといったらない
Detailed explanation
The ~といったらない grammar point is used to emphasize the high degree or intensity of an action or state. It can be translated as “nothing can be more ... than this” or “it’s extremely...”. It conveys that something is so intense or extreme that it cannot be adequately described.
Examples
Kyou wa samui to ittara nai.
It’s extremely cold today.
Kanojo no ryouri no oishisa to ittara nai.
Nothing can be more delicious than her cooking.
Kono ko no atama no yosa da to ittara nai.
This child is unbelievably smart.
Kare no namakeppuri da to ittara nai.
Nobody could be lazier than him.
Practice
Grammar content sourced from hanabira.org.