What is the meaning of Nirmala?

1. What is the meaning of Nirmala? 

It is the Name of the Goddess which means without impurity. Shri Mataji gave a comprehensive explanation of Her name in a conference in Marathi translated into English: (This was then translated into French, and back again into English)

Nirmala integrates the three gunas. NI for the right channel, LA for the left 
and MA for Sushumna. 

"The first part, NIH means negation. It is the negation. It is the 
negation of existence, which is illusion, maya (...) NIH shakti is the power of
Shri Brahmadeva, ie Shri Shakti Saraswati. NIH implies complete 
detachment. You must become completely detached. " 
"LA comes from Lalita which is a blessing and a weapon of the Goddess. When the Shakti 
becomes Lalita, meaning active, then the vibration increase in Her, these
are the vibrations you feel in the palm of your hands (...). When the 
power of love becomes active, it becomes LA Shakti. It is LA Shakti that does
all the work, it is thanks to Her that you have your Realisation. " 
"Shakti is the power of love. It is activated by NIH Shakti which is the 
power of action. " 
"The syllable MA is between NIH and LA. MA is the syllable of Mahalakshmi which is the 
power of the Dharma and the power of evolution. In MA Shakti, you must 
understand, assimilate and this requires mastery. 
For example, an artist conceives the idea of his creation with LA Shakti, he 
constructed with NIH Shakti and then uses MA Shakti to bring it to his original idea while improving it. This improvement is evolution and this implies an effort. 
The two powers (NIH and LA) only become active when you develop
by the power of evolution. You must fully understand and develop MA
Shakti. You must achieve a balance between the NIH and MA Shaktis." 
"MA is the first syllable of Mataji, Mother. This has been made possible only through
MA Shakti within me. This would not have been possible with only the LA
Shakti and Shakti NIH. I have come with these three powers but it is MA  Shakti
which is at the summit." 
(Shri Mataji Nirmala Devi) 
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