hygro-

hygro-
  (ˈhaɪgrəʊ)
  before a vowel also hygr-, repr. Gr. ὑγρο-, ὑγρ-, combining form of ὑγρός wet, moist, fluid: extensively employed in Greek; the English compounds are mostly scientific terms of recent formation. The chief of these are hygrometer and hygroscope, with their derivatives. Other words in hygro- are the following:
  (The υ in Gr. is short, and the etymological pronunciation would be (hɪg-); but the tendency to take y as long i, has in this, as in other cases, prevailed against the etymology.)
  † hygroˈbaroscope [see baroscope], an instrument for measuring the specific gravity of liquids; a hydrometer. hygroblepharic (-blɪˈfærɪk) a. [Gr. βλέϕαρον eyelid], moistening the eyelid; applied to the lachrymal duct. † hygrocirsocele (-ˈsɜːsəʊsiːl), a cirsocele accompanied with dropsy of the scrotum. ˈhygrodeik (-daɪk) [Gr. δεικνύναι to show], a form of hygrometer consisting of a wet-bulb and a dry-bulb thermometer together with a scale on which the degree of humidity is shown by an index whose position depends on the height of the mercurial column in each. ˈhygrograph (-grɑːf, -græf) [Gr. γραϕος- writing], an instrument for registering automatically the variations in the humidity of the air (Webster, 1864). hygrophanous (-ˈɒfənəs) a. Bot. [Gr. ὑγροϕανής], of moist appearance; also, appearing translucent when moist and opaque when dry (Syd. Soc. Lex. 1886). ˈhygroplasm (-plæz(ə)m) Biol. [Gr. πλάσµα a thing moulded], ‘Nägeli's term for the fluid part of protoplasm’ (Syd. Soc. Lex.). † hygrostatics (-ˈstætɪks) [see statics], ‘the art of finding the specific weights of moist bodies’ (Bailey, 1731). hygrothermal (-ˈθɜːməl) a. [Gr. θερµός warm], relating to moisture and heat. hygroˈthermograph, an instrument that records the temperature and humidity of the air on a single chart.

Oxford English Dictionary