helio

Helio- is a combining form used like a prefix meaning “sun.” It is frequently used in a variety of scientific and technical terms.

Helio- comes from Greek hḗlios, meaning “sun.” The Latin cognate, sōl, is the source of several words related to the sun, such as solar and solstice.

What are variants of helio-?

When combined with words or word elements that begin with a vowel, helio- becomes heli-, as in heliencephalitis. Want to know more? Read our Words That Use article for heli-.

One example of a term that features the form helio- is heliolatry, meaning “worship of the sun.”

We know helio- means “sun,” and the -latry portion of the word refers to “worship,” from Greek -latria. Heliolatry literally translates to “sun worship.”

What are some words that use the combining form helio-?

• heliodor (using the equivalent form of helio- in German)
• heliogram
• heliograph
• heliometer
• heliophyte
• heliosphere
• heliotype

What are some other forms that helio- may be commonly confused with?

• helic-
• helico-

The combining form -phyte means “plant with a specific habitat.” With this in mind, what kind of plant does the botanical term heliophyte refer to?