flexibleness vs plasticity

flexibleness and plasticity both are nouns.

Word	Noun	Adjective	Verb	Adverb
flexibleness	Yes	No	No	No
plasticity	Yes	No	No	No

As nouns, plasticity is a hypernym of flexibleness; that is, plasticity is a word with a broader meaning than flexibleness:

flexibleness: the property of being flexible; easily bent or shaped
plasticity: the property of being physically malleable; the property of something that can be worked or hammered or shaped without breaking

Other hypernyms of flexibleness include malleability.

flexibleness (noun)	plasticity (noun)
the property of being flexible; easily bent or shaped	the property of being physically malleable; the property of something that can be worked or hammered or shaped without breaking
the quality of being adaptable or variable