This is the 1465th most frequent Japanese word.
脱
"脱" means "to take off," "remove," or "escape."
In this sentence, 「脱帽」 (datsubō) is used where 「脱」 (datsu) means 'to remove,' connected to the concept of taking off a hat as a sign of respect or gratitude.
彼は脱帽して感謝の気持ちを示した。
He expressed his gratitude by removing his hat.
Here, 「脱サラ」 (datsu-sara) uses 「脱」 to signify leaving behind, specifically leaving the corporate salary worker lifestyle to pursue independence.
彼女はこの会社を退職して脱サラを目指したい。
She wants to resign from this company and aim for an independent career.
In the sentence, 「脱却」 (dakkyaku) uses 「脱」 with the meaning of 'breaking away' from a particular state, such as dependency.