helio-, heli-

(Greek: sun)

heliothermometer
An early form of solar collector, invented by Swiss scientist Horace-Benedict de Saussure in about 1780.
heliothermy
1. The process of regulating body temperature primarily by means of heat gain from direct solar radiation, as in reptiles and amphibians.
2. The utilization of solar radiation to produce useful energy.
heliotrope (s) (noun), heliotropes (pl)
1. A plant that turns or bends so that it faces the sun.
2. Any of the genus Heliotropium, a herb or shrub of the borage family.
3. A heliograph that is capable of reflecting solar rays over long distances.
heliotropic (adjective)
1. Oriented toward sunlight or other light.
2. Describing a plant that grows, or moves, toward the sun.
3. The description of a device that follows the sun's apparent movement across the sky.
heliotropic wind
A wind component that adapts (by subtle shifting) to the diurnal shift of the sun's position, in consonance with the east-to-west progression of daytime surface heating.
heliotropism (s) (noun), heliotropisms (pl)
1. Plant movement or orientation in response to the location of sun light.
2. The reversible phenomenon of color change in a solid as the result of exposure to sun light.
helioxerophile
A reference to desert organisms that thrive best in both strong sunlight and dry conditions.
helioxerophilous
A reference to desert creatures and plants that thrive well in both strong sunlight and drought situations.
helioxerophily
The preference of desert organisms that thrive best in both strong sunlight and dry conditions.
Heliozoa, Heliozoia
Sun animalcules, an order of free-living aquatic protozoans in the subclass Actinopoda; spherical with radiating filopedia, they feed on other protozoans and rotifers (any of various minute multicellular aquatic organisms of the phylum Rotifera, having at the anterior end a wheel-like organ, or ring of cilia, for feeding and locomotion.
heliozoan
A free-living, usually freshwater, protozoan that has a spherical shell and radiating projections.

Heliozoa, or sun animalcules, are roughly spherical amoeboids with many stiff, microtubule-supported projections called axopods radiating outward from the cell surface.

These give them the characteristic sun-like appearance for which they are named, and are variously used for capturing food, sensation, movement, and attachment. They may be found in both fresh water and marine environments.

orthoheliotropic
Referring to an orientation response towards sunlight.
orthoheliotropism
An orientation response towards sunlight.
paraheliotropism
Movement of leaves to avoid or to minimize exposure to sunlight.
parhelion
A bright spot on a solar halo sometimes appearing on either side of the sun, often on a luminous ring or halo.

Also called mock suns, they are bright, colorful light patches which appear in ice clouds 22° or more to either side of the sun.

At sunrise and sunset, the angular separation from the sun is exactly 22°. When the Sun is high, the parhelions may appear diamond-shaped, and no parhelion can occur if the sun is higher than 61°.

Related "sun" word family: sol-.