|Easton's Bible Dictionary|
A height, a name used simply to denote a high place where the Jews worshipped idols (Ezek. 20:29). The plural is translated "high places" in Numbers 22:41 and Ezek. 36:2.
Int. Standard Bible Encyclopedia
ba'-ma, ba'-ma (bamah, "high place"): The word appears in Ezekiel 20:29 where reference is made to former "high-place worship," the prophet speaking with contempt of such manner of worship. Ewald suggests a play of words, ba', "come" and mah, "what," "what (mah) is the high place (ba-mah) whereunto ye come (ba')?" It is possible that reference is made to a prominent high place like the one at Gibeon (compare 1 Kings 3:4 1 Chronicles 16:39; 1 Chronicles 21:29 2 Chronicles 13) for which the name "Bamah" was retained after the reform mentioned by the prophet.
Bamah (1 Occurrence)
Ezekiel 20:29 Then I said to them, What does the high place where you go mean? So its name is called Bamah to this day. (WEB KJV JPS ASV BBE DBY WBS NAS RSV NIV)