General synonyms:
* Characteristic
* Attribute
* Feature
* Quality
* Trait
* Property (this can be used interchangeably with "physical property" in many cases)
More specific synonyms:
* Material property (focuses on the composition and structure of a material)
* Mechanical property (refers to how a material behaves under stress and strain)
* Optical property (describes how light interacts with a material)
* Thermal property (deals with how a material reacts to heat)
* Electrical property (relates to how a material conducts electricity)
The best synonym to use will depend on the specific context and what you want to emphasize.
