Synonyms for Prostrate (same or very similar meaning)
WordNet sense 1 (get into a prostrate position, as in submission):
bow down
WordNet sense 2 (lying face downward):
prone
WordNet sense 3 (stretched out and lying at full length along the ground):
flat
WordNet sense 4 (not upright in position or posture):
unerect
From the ODE community, based on WordNet
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