1870, see thermo- + plastic (adj.). As a noun from 1929.
Entries linking to thermoplastic
thermo-
before vowels therm-, word-forming element meaning "hot, heat, temperature," used in scientific and technical words, from Greek thermos "hot, warm," therme "heat" (from PIE root *gwher- "to heat, warm").
plastic adj.
1630s, "capable of shaping or molding a mass of matter," from Latin plasticus, from Greek plastikos "fit for molding, capable of being molded into various forms; pertaining to molding," also in reference to the arts, from plastos "molded, formed," verbal adjective from plassein "to mold" (see plasma). Related: Plastically.
Hence "capable of change or of receiving a new direction" (1791). The surgical sense of "remedying a deficiency of structure" is recorded by 1839 (in plastic surgery). Meaning "made of plastic" is from 1909; this was picked up in counterculture slang and given an extended meaning "false, superficial" (1963). Plastic explosive (n.) "explosive material with a putty-like consistency" is attested from 1894.