Gel

Highly viscous liquid exhibiting a kind of semi-solid behavior

A gel is a semi-solid that can have properties ranging from soft and weak to hard and tough. Gels are defined as a substantially dilute cross-linked system, which exhibits no flow when in the steady state, although the liquid phase may still diffuse through this system. Gels are mostly liquid by mass, yet they behave like solids because of a three-dimensional cross-linked network within the liquid.

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