mutable
Meaning: able to change
Usage: Because fashion is so mutable, what is trendy today will look outdated in five years.
malleable
Meaning: capable of being shaped or transformed
Usage: Maximillian’s political opinions were so malleable that anyone he talked to was able to change his mind instantly.
dynamic
Meaning: actively changing
Usage: The parents found it hard to keep up with the dynamic music scene with which their children had become very familiar.
immutable
Meaning: not changeable
Usage: The laws of physics are immutable and constant.
protean
Meaning: able to change shape; displaying great variety
Usage: Among Nigel’s protean talents was his ability to touch the tip of his nose with his tongue.