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removing one's hat
admiring (someone) greatly; taking one's hat off to
国歌斉唱の際は脱帽してください。
Please remove your hat during the national anthem.
彼の努力には脱帽するしかない。
One can only take one's hat off to his efforts.
その技術力には脱帽だ。
I take my hat off to that level of skill.