Hydrogels

Part of speech: noun

Definitions

1. A category of materials formed from polymeric networks that can retain large volumes of water
2. These substances, often jelly-like, are used in areas like medicine and agriculture for their water-absorbing properties
3. Materials composed of cross-linked polymers capable of holding substantial amounts of water within their structures

Etymology: Hydrogels are named by simply joining two older building blocks. The first part, "hydro-", comes from ancient Greek "hudōr", meaning water, which English has used in combining forms like hydraulic and hydrogen. The second part, "gel", is a clipping of "gelatin," itself traced back through French "gélatine" and Italian "gelatina" to Latin "gelāre," meaning to freeze or congeal. So the word literally describes a water-filled substance that has gelled, the same idea that makes gelatin dessert wobble. The word is plural here because it refers to more than one material, and "hydrogel" is the singular form. Its structure is entirely transparent: a compound of "hydro-" and "gel," with no separate history of its own before that.