Meander is the Greek word for "key" and the Meander Tiara was the only tiara passed into the royal family from Prince Philip's family (which was rather impoverished).
It belonged to his mother, who was born Princess Alice of Battenburg - after she married Prince Andrew of Greece, she was known as Princess Andrew of Greece. Here she is wearing the tiara in 1914:
She passed it to her granddaughter Princess Anne:
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Who gave it to her daughter Zara Phillips
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