upá-stha m. ‘the part which is under’, lap, middle or inner part of anything, a well-surrounded or sheltered place, secure place, [RV.]; [AV.]; [VS.]; [AitBr.]; [ŚBr.] &c.
(upasthaṃ-√ kṛ, to make a lap, sit down with the legs bent, [AitBr. viii, 9, 5]; [ĀśvGṛ.]; [ŚāṅkhŚr.]; upasthe-√ kṛ, to take on one's lap, [ŚBr. iii])
upá-stha m. n. the generative organs (esp. of a woman), [VS. ix, 22]; [ŚBr.]; [MBh.]; [Mn.]; [Yājñ.] &c.
the haunch or hip
the anus, [L.]
upa-sthá mfn. standing upon, [AV. xii, 1, 62]
standing by the side of, being near at hand, near, [L.]