1899, as a chemical term, short for gelatin and perhaps influenced by jell. The invention of this word is credited to Scottish chemist Thomas Graham (1805-1869). Hair-styling sense is from 1958. The verb meaning "to become a gel" is attested by 1902; figurative sense is from 1958. Related: Gelled; gelling.
A colloid in which the disperse phase combines with the dispersion medium to produce a semisolid material. v. gelled, gel·ling, gels
To become a gel.
To convert a sol into a gel.