1. Capable of being shaped or formed: plastic material such as clay. See synonyms at malleable.
2. Relating to or dealing with shaping or modeling: the plastic art of sculpture.
3. Having the qualities of sculpture; well-formed: "the astonishing plastic beauty of the chorus girls" (Frank Harris).
4. Giving form or shape to a substance: the plastic forces that create and wear down a mountain range.
5. Easily influenced; impressionable.
6. Made of a plastic or plastics: a plastic garden hose.
7. Physics. Capable of undergoing continuous deformation without rupture or relaxation.
8. Biology. Capable of building tissue; formative.
9. Marked by artificiality or superficiality; synthetic: a plastic world of fad, hype, and sensation.
10. Informal. Of or obtained by means of credit cards: plastic money.

1. Any of various organic compounds produced by polymerization, capable of being molded, extruded, cast into various shapes and films, or drawn into filaments used as textile fibers.
2. Objects made of plastic.
3. Informal. A credit card or credit cards: would accept cash or plastic in payment.

[Latin plasticus, from Greek plastikos, from plastos, molded, from plassein, to mold.]

The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.