dehydro-

1. a combining form meaning “dehydrogenated,” used in the formation of compound words:

   dehydrochlorinate.

Words That Use dehydro-

What does dehydro- mean?

Dehydro– is a combining form used like a prefix meaning “dehydrogenated.” Dehydrogenated is a term meaning “to remove hydrogen from (a compound).” It is occasionally used in scientific terms, especially in chemistry.

Dehydro– comes from the word dehydrogenate. The prefix de– means “removal” or “separation.” Hydrogenate means “to combine or treat with hydrogen.” The first element in hydrogen, hydro-, derives from Greek hýdōr, meaning “water.” To learn more, check out our Words That Use article on the combining form hydro–.

Examples of dehydro-

One example of a term from chemistry that features the form dehydro– is 7-dehydrocholesterol, “a provitamin present in the skin of humans as well as the milk of mammals that becomes vitamin D3 when exposed to ultraviolet light.”

The dehydro– part of the word means “dehydrogenated.” Cholesterol is a compound that occurs in all animal tissues. Dehydrocholesterol literally means “dehydrogenated cholesterol.”

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

• dehydrochlorinase
• dehydrochlorinate
• dehydrocorticosterone
• dehydroepiandrosterone
• dehydrofreeze
• dehydroretinol

What are some other forms that dehydro– may be commonly confused with?

• de-
• dendro-
• hydro-
• hydroxy-

Break it down!

Retinol is also known as “vitamin A.” With this in mind, what is the chemical compound dehydroretinol?