[hypo-] or hyp- prefix [ME ypo-, fr. OF, fr. LL hypo-, hyp-, fr. Gk, fr. hypo--more at up] 1: under: beneath: down "hypoblast" "hypodermic"
2: less than normal or normally "hypesthesia" "hypotension"
3: in a lower state of oxidation: in a low and usu. the lowest position in a series of compounds "hypochlorous acid" "hypoxanthine"