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stern; grave; austere; imposing; dignified; formidable; solemn; majestic
strict (e.g. security); severe; firm; rigid; rigorous
厳めしい顔つきの警備員がいた。
There was a guard with a stern expression.
城門の構えは実に厳めしかった。
The structure of the castle gate was truly imposing.
彼の表情は思ったほど厳めしくない。
His expression isn't as stern as I expected.