- hypothermia (n.)
- 1877, Modern Latin, from hypo- "under" (see hypo-) + Greek therme "heat" (see thermal).
- hypotheses (n.)
- plural of hypothesis.
- hypothesis (n.)
- 1590s, from Middle French hypothese and directly from Late Latin hypothesis, from Greek hypothesis "base, basis of an argument, supposition," literally "a placing under," from hypo- "under" (see sub-) + thesis "a placing, proposition" (see thesis). A term in logic; narrower scientific sense is from 1640s.
- hypothesise (v.)
- chiefly British English spelling of hypothesize; for suffix, see -ize. Related: Hypothesised; hypothesising.
- hypothesize (v.)
- 1738, from hypothesis + -ize. Related: Hypothesized; hypothesizing.
- hypothetical (adj.)
- 1580s, from Greek hypothetikos "pertaining to a hypothesis," from hypothesis (see hypothesis). Related: Hypothetically; hypothetic.
- hypotonia (n.)
- 1876, medical Latin, from hypo- + Greek tonos "tone" (see tenet).
- hypotonic (adj.)
- 1873, from hypo- + tonic.
- hypoxia (n.)
- 1941, from hypo- + oxygen. Related: Hypoxic.
- hypsi-
- word-forming element meaning "on high," from Greek hypsi "aloft, on high," related to hypsos "height;" cognate with Sanskrit os "above, over," Old Church Slavonic vysoku "high."
- Hyrcania
- ancient region southeast of the Caspian Sea, from Greek Hyrkania, said to be from an Indo-European *verkana "country of wolves" [Zonn, I., et al., "The Caspian Sea Encyclopedia," 2010]
- hyssop (n.)
- Old English ysope, from Irish Latin hysopus, from Greek hyssopos, a plant of Palestine, used in Jewish purification rites, from Hebrew 'ezobh (cf. Syriac zupha, Arabic zufa).
- hysterectomy (n.)
- 1886, coined in English from Greek hystera "womb" (see uterus) + -ectomy.
- hysteresis (n.)
- 1805, from Greek hysteresis "a coming short, a deficiency."
- hysteria (n.)
- 1801, coined in medical Latin as an abstract noun from hysteric (see hysterical).
- hysteric (adj.)
- 1650s, from Latin hystericus, from Greek hysterikos “belonging to the womb” (see hysterical). As a noun from 1751.
- hysterical (adj.)
- 1610s, from Latin hystericus "of the womb," from Greek hysterikos "of the womb, suffering in the womb," from hystera "womb" (see uterus). Originally defined as a neurotic condition peculiar to women and thought to be caused by a dysfunction of the uterus. Meaning "very funny" (by 1939) is from the notion of uncontrollable fits of laughter. Related: Hysterically.
- hysterics (n.)
- 1727, from hysterical. Sometimes in 19c. jocularly folk-etymologized as high-strikes (1838).
- hysteron proteron
- 1560s, from Late Latin, from Greek, literally "the latter (put as) the former." A figure of speech in which what should come last is put first, from hysteron, neuter of hysteros "latter, second, after" (from PIE *ud-tero-, from root *ud- "up, out;" see out) + proteron, neuter of proteros "before, former," from PIE *pro-, from root *per- (1) "forward, through" (see per).