Paschimottanasana is a compound of four words. Shadow yoga

Paschimottanasana is a compound of four words - paschima, ut, an and asana - none of which refer to forward bending.‘ Paschima’ means west, ‘ut’ means intense and ‘an’ refers to the acquisition of a particular shape. The full meaning of the name therefore refers to the folding in of the sun on the western horizon. The name suggests that one must fold at the region of the navel in such way that its energy is pulled towards the bladder and the rectum. 

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