Just for a change, this obscure word comes from entomology. Insects can be very irritating, can't they?!
Main Entry: ma·la
Function: noun
Inflected Form(s): plural ma·lae
Etymology: New Latin, from Latin, jaw, cheek -- more at MAXILLA
1 : a single lobe of the maxilla of an insect
2 a : the grinding surface of a mandible of an insect b : the third segment of a mandible of some myriapods
Citation format for this entry:
"mala." Webster's Third New International Dictionary, Unabridged. Merriam-Webster, 2002.
http://unabridged.merriam-webster.com (1 Oct. 2007).