[hee-lee-uh-sfeer] /ˈhi li əˌsfɪər/
the region around the sun over which the effect of the solar wind extends.
the region around the sun outside of which the sun’s influence is negligible and interstellar space begins
The large, roughly elliptical region of space around the Sun through which the solar wind extends and through which the Sun exerts a magnetic influence. The heliosphere extends well beyond the orbits of the planets, and its shape and extent fluctuate with changes to the solar wind and other influences. ◇ The boundary between the heliosphere and interstellar space is known as the heliopause.
[hee-lee-uh-stat] /ˈhi li əˌstæt/ noun 1. an instrument consisting of a mirror moved by clockwork, for reflecting the sun’s rays in a fixed direction. /ˈhiːlɪəʊˌstæt/ noun 1. an astronomical instrument used to reflect the light of the sun in a constant direction
[hee-lee-oh-tak-sis] /ˌhi li oʊˈtæk sɪs/ noun, Biology. 1. movement of an organism toward or away from sunlight. /ˌhiːlɪəʊˈtæksɪs/ noun 1. movement of an entire organism in response to the stimulus of sunlight
[hee-lee-oh-ther-uh-pee] /ˌhi li oʊˈθɛr ə pi/ noun 1. treatment of disease by means of sunlight. /ˌhiːlɪəʊˈθɛrəpɪ/ noun 1. the therapeutic use of sunlight
[hee-lee-uh-trohp, heel-yuh- or, esp. British, hel-yuh-] /ˈhi li əˌtroʊp, ˈhil yə- or, esp. British, ˈhɛl yə-/ noun 1. any hairy plant belonging to the genus Heliotropium, of the borage family, as H. arborescens, cultivated for its small, fragrant purple flowers. 2. any of various other plants, as the valerian or the winter heliotrope. 3. any […]