Greet informally at General Assembly, using system of Hindu philosophy (4)
I believe the answer is:
yoga
'hindu philosophy' is the definition.
(I've seen this in another clue)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for yoga that I've seen before include "path to enlightenment" , "Hindu body work" , "Hindu philosophy of tranquility through physical exercise" , "System of exercises for bodily or mental control" , "Spiritual exercise discipline" .)