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namma hole

American  
[nam-uh hohl] / ˈnæm ə ˌhoʊl /

noun

Australian.
  1. gnamma hole.


namma hole British  
/ ˈnæmə /

noun

  1. a natural well in a rock

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of namma hole

C19: from a native Australian language