The island had gone through several name changes before it became known as Sentosa, which means PEACE and TRANQUILITY in Malay.
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Up until 1830, it was called Pulau Panjang, literally translated as LONG ISLAND. It was also known as "the island behind death," or Pulau Blakang Mati, with Blakang Mati also being the name of a hill on the island.