Dehydro

Part of speech: adjective, verb

Definitions

1. A chemical compound with fewer hydrogen atoms than its original form, often created through the removal of water or hydrogen
2. A substance resulting from the loss of one or more hydrogen atoms during a chemical reaction, typically involving dehydration
3. Referring to a molecular structure in which hydrogen has been removed, frequently used in organic chemistry to denote specific transformations

Etymology: Chemists used "dehydro-" as a prefix for a loss of hydrogen, not of water. The Greek "hydōr" (water) gave us the prefix "hydro-," which in chemistry came to mean hydrogen itself. That shift happened because Antoine Lavoisier named hydrogen in 1783 from "hydōr" and "-gen" (producer), since burning it produced water. The prefix "de-" comes from Latin and means removal or reversal, so "dehydro-" literally means "removal of hydrogen." "Dehydration" follows the older sense of "hydro-" as water. Removing water from a substance is dehydration, but a dehydro- compound has lost hydrogen atoms, which is a different chemical change. The two words overlap because water contains hydrogen, which is why the terms are easy to confuse. The prefix is a combining form rather than a true adjective or verb, so it appears only inside longer chemical names.

Synonyms: dehydrated, anhydrous, dry, desiccated, dewatered

Antonyms: hydrated, wet, moist, damp