We don't have synonyms for chaldaea yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are haldea, chamaea and chaldea.
(n) :
Alternative form of Chaldea: (historical) An ancient geographic region of West Asia, in the southern portion of Babylonia in modern eastern Iraq and southwestern Iran, lying chiefly on the right bank of the Euphrates, but commonly used to refer to the whole of the Mesopotamian plain [(historical) An ancient geographic region of West Asia, in the southern portion of Babylonia in modern eastern Iraq and southwestern Iran, lying chiefly on the right bank of the Euphrates, but commonly used to refer to the whole of the Mesopotamian plain.]
(n) :
Alternative form of Chaldea: (historical) An ancient geographic region of West Asia, in the southern portion of Babylonia in modern eastern Iraq and southwestern Iran, lying chiefly on the right bank of the Euphrates, but commonly used to refer to the whole of the Mesopotamian plain [(historical) An ancient geographic region of West Asia, in the southern portion of Babylonia in modern eastern Iraq and southwestern Iran, lying chiefly on the right bank of the Euphrates, but commonly used to refer to the whole of the Mesopotamian plain.]